JJ 2011 J2/H1 Physics (8866)
|
|
- Conrad Cameron
- 7 years ago
- Views:
Transcription
1 8. Wave Motion Content 1. Progressive Waves 2. Transverse and Longitudinal Waves 3. Polarisation 4. Determination of frequency and wavelength Learning Outcomes: Candidates should be able to: (a) (b) (c) (d) show an understanding and use the terms displacement, amplitude, phase difference, period, frequency, wavelength and speed. deduce, from the definitions of speed, frequency and wavelength, the equation v = fλ. recall and use the equation v = fλ. show an understanding that energy is transferred due to a progressive wave. (e) recall and use the relationship, intensity (amplitude) 2. (f) (g) (h) (i) analyse and interpret graphical representations of transverse and longitudinal waves. show an understanding that polarisation is a phenomenon associated with transverse waves. determine the frequency of sound using a calibrated c.r.o. determine the wavelength of sound using stationary waves. Acknowledgements: 1. Comprehensive Physics for A level (3 rd edition) Vol.2 KF Chan, Charles Chew, SH Chan (Federal Study Aids) 2. Fundamentals of Physics (6 th edition) Halliday, Resnick, Walker (John Wiley & sons, Inc.). 3. Notes Wave Motion 2009 by FS Chin JJ J2 H2 Wave Motion Notes by KW Chong JJ cfs / kpl Page 1 of 24
2 Waves vs. Particles Two ways to get in touch with a friend in a distant city are to write a letter and to use the telephone. The first choice (the snail-mail) involves the concept of a particle : a material object moves from one point to another, carrying with it information and energy. The 2 nd choice (the telephone) involves the concept of waves. The information and energy move from one point to another but no material object makes that journey. In the telephone call, a sound wave carries your message from your vocal cords to the telephone. There, an electromagnetic wave takes over, passing along a copper wire or an optical fiber or through the atmosphere (satellite). At the receiving end, there is another sound wave, from a telephone to your friend s ear. Although the message is passed, nothing that you have touched reaches your friend. It often happens that the wave flees the place of its creation, while the water does not: like the wave made in a field of grain by the wind, where we see the waves running across the field while the grain remains in place. ~ Leonardo da Vinci. Particle and wave are the 2 great concepts in classical physics, although the concepts are very different. The word particle suggests a tiny concentration of matter capable of transmitting energy. The word wave suggests a broad distribution of energy, filling the space through which it passes. Wave Production 1. The source of any wave is a vibration or oscillation. 2. A wave is a mechanism for the transfer of energy from one point to another without the physical transfer of any material between the points. Types of Waves There are 3 main types: 1. Mechanical Waves. These waves are most familiar because we encounter them almost constantly. Examples include water waves, sound waves and seismic waves. The wave motion is transmitted by the particles of the medium oscillating to and fro. Main features : (i) Newton s laws govern them; (ii) they can only exist within a material medium (e.g. water, air & rock) 2. Electromagnetic (EM) waves. These are less familiar, but we use them constantly. Common examples include visible and ultraviolet light, radio and television waves, microwaves, x-rays and radar waves. The wave motion is in the form of varying electric and magnetic fields. Main features : (i) these waves require no material medium to exist (ii) All electromagnetic waves travel through a vacuum at the same speed, c (speed of light), i.e. c = m s -1 3 x 10 8 m s Matter waves. Although these waves are commonly used in modern technology, their type is probably very unfamiliar to us. These waves are associated with electrons, protons and other fundamental particles, even atoms and molecules. Because we commonly think of these things as constituting matter, they are called matter waves. (Not in your syllabus). cfs / kpl Page 2 of 24
3 Visualising Waves A typical way to visualize water waves is to use a ripple tank experiment. The set up is as shown below. Fig 1(a) Fig 1(b) Learning points: Our usual representation of waves is typically sinusoidal curves, as seen in Fig 1(a), which is the wave pattern as seen from the side view. Another common representation of waves is seen in Fig 1(b), which is the wave pattern projected by a light source from the top (i.e. Top View). The dark lines indicate the crests of the wave. a) Show an understanding and use the term displacement, amplitude, phase difference, period, frequency, wavelength and speed. 1. Displacement, x Displacement of a particle is its distance in a given direction from its equilibrium position. (Similar as in SHM. It is NOT the displacement of the whole wave.) 2. Amplitude, A Amplitude is the magnitude of the maximum displacement of a particle from its equilibrium position. It is a scalar. 3. Period, T The period of oscillation of a wave is the time taken for a particle (element) in the wave to complete one oscillation. cfs / kpl Page 3 of 24
4 4. Frequency, f Frequency of a wave is the number of oscillations per unit time made by a particle (element) in the wave. The frequency of a wave is the same as the frequency of its source. It is independent of the medium through which the wave propagates. It is related to period, T, by f 1 ω = = T 2π where ω = angular frequency. 5. Wavelength, λ Wavelength of a wave is the shortest distance between two points which are in phase. 6. Speed, v Speed of a wave is the distance travelled by the wave per unit time. 7. Phase and Phase Difference, φ Phase difference between two points in a wave is the difference between the stages of oscillations, expressed in terms of an angle. (e.g. Two points half a wavelength apart has a phase difference of π radians) 1. Two points being in the same phase means that they are in the same state of disturbance at the same time (e.g. the points x x and y y in the diagram above). They are said to be in phase. Their phase difference is zero. 2. Two crests or two troughs are in phase, whereas a crest and an adjacent trough are out of phase by 180 or π rad. They are said to be anti-phase. Their phase difference is 180 or π rad. cfs / kpl Page 4 of 24
5 3. The phase difference, φ, between two particles in a wave (e.g. particle P and another particle B, below) separated by distance x, is given by x φ = λ 2π The L.H.S is a ratio of angles in radians The denominator is the angle for a complete oscillation. The R.H.S is a ratio of distance travelled by the wave. The denominator is the distance travelled by the wave in the time for a complete oscillation, the wavelength λ. 4. The phase difference, φ, between two oscillations separated by a time t is given by φ t 2π = T Now the R.H.S. is a ratio of time. The denominator is the time for a complete oscillation, the period T. (b) Deduce, from the definitions of speed, frequency and wavelength, the equation v = fλ. Speed, v, is the distance travelled per unit time. In the time of one period, T, the wave travels a distance of one wavelength, λ. So the speed of a wave motion can be expressed as distance travelled v = = λ (1) time taken T Frequency f is related to period T by the relation f = 1 T (2) From the relations (1) and (2) above, the speed of a wave motion can hence be expressed as v = fλ cfs / kpl Page 5 of 24
6 (c) Recall and use the equation v = fλ Example 1 Visible light has wavelengths between 400 nm and 700 nm, and its speed in a vacuum is m s -1. What is the maximum frequency of visible light? Solution: From v = fλ, the frequency f = λ v, i.e. f is inversely proportional to λ. For maximum frequency, minimum wavelength should be used. Hence, 8 1 v 3 10 m s f max = = 9 λmin m = Hz. Example 2 A sound wave of frequency 400 Hz is travelling in a gas at a speed of 320 m s -1. What is the phase difference between two points 0.2 m apart in the direction of travel? Solution: Wavelength, λ = v 1 f = 320 m s 400 Hz = 0.80 m φ 2 π = x 0.2 m = λ 0.8 m = 1 4 φ = π 2 rad Example 3 The speed of electromagnetic (EM) waves (which include visible light, radio and x-rays) in vacuum is 3.0 x 10 8 m s -1. a) Wavelengths of visible light waves range from about 400 nm in the violet to about 700 nm in the red. What is the range of frequencies of these waves? b) The range of frequencies for short-wave radio (e.g. Class 95 FM) is 1.5 to 300 MHz. What is the corresponding wavelength range? c) X-ray wavelengths range from about 5.0 nm to about 1.0 x 10-2 nm. What is the frequency range for x-rays? Solution v a) Using v = fλ f = λ x x10 14 fred = = 4.29x10 Hz & f x Hz 9 violet = = x10 400x10 Hence, range of frequencies for visible light is from 4.29 x Hz to 7.50 x Hz. cfs / kpl Page 6 of 24
7 b) From v = fλ λ = v f 8 8 3x10 3x10 λ1 = = 200 m & λ 6 2 = = 1m 6 1.5x10 300x10 Hence, wavelength range is from 1 m to 200 m v c) From v = fλ f = λ x x10 19 f1 = = 6.0x10 Hz & f 3.0x10 Hz 9 2 = = x10 1.0x10 Hence, frequency range for x-ray is from 6.0 x to 3.0 x Hz. Example 4 What happens to the speed, frequency and wavelength of light when it enters glass from air? speed frequency wavelength A decreases increases unchanged B increases unchanged increases C unchanged decreases decreases D decreases unchanged decreases Solution: Frequency of a wave is the same as the frequency of its source, independent of the medium. Speed of light is highest in vacuum (or air). Ans: D (d) Show an understanding that energy is transferred due to a progressive wave. Oscillation (or oscillatory motion) refers to the to-and-fro motion of a particle about an equilibrium position. The oscillatory motion of the particle is a continuous exchange of potential and kinetic energy of the particle. It is illustrated by a graph of displacement from that equilibrium position, y, vs time, t. Wave refers to the combined motion of a series of linked-particles, each of which is originally at rest at its respective equilibrium position. Starting from the oscillation of the first particle about its equilibrium position, the energy of the oscillation is passed to the second particle, which in turn is passed to the third particle and subsequent particles in the series of linked-particles. So wave motion is the motion of energy passed from one particle to the next in a series, through oscillatory motion of these particles, in sequence. cfs / kpl Page 7 of 24
8 Examples: (1) Sound wave: When a sound wave is propagated from a tuning fork to an ear of a person some distance away, the vibration of the fork sets the air layer next to it into vibration. The second layer of air is then set into vibration by the transfer of energy from the first layer. This transfer of energy continues for subsequent layers until the layer of air next to the ear is also set into vibration, which in turn vibrates the ear-drum of the ear, enabling the person to hear the sound originated from the tuning fork. There is no net transfer of air particles from the tuning fork to the ear. The ear-drum in the ear can vibrate because energy has been transferred to it from the tuning fork, through the sequential vibration of the layers of air between the tuning fork and the ear. (Diagram above) This sequential vibration of the layers of air forms regions of compression (where air layers are closer to each other) and regions of rarefaction (where air layers are further apart). The one-way movement of such regions from the tuning fork to the ear signifies the propagation of sound wave energy. (2) Wave in a rope: The wave travelling in a rope may originate from the vibration of the first particle at one end of the rope. The energy of the vibrating first particle is transferred to the second particle, setting it into vibration. This transfer of energy continues to subsequent particles in the rope until it reaches the other end of the rope. (3) Water wave: The energy of the vibrating water molecules is transferred to subsequent molecules along the surface of water, causing these molecules further from the vibrating source to be set into up-down motion. cfs / kpl Page 8 of 24
9 The examples (1), (2) and (3) are examples of progressive waves, where energy is transferred from one region to another region through sequential vibration of a series of linked-particles. The energy of a first vibrating particle is propagated along a series of linked-particles to another region. Sound energy is propagated from the tuning fork to the ear, energy from one end of a rope is propagated to the other end, and energy from one region of water surface next to a vibrating source is propagated to another region in the ripple tank. (e) Recall and use the relationship, intensity (amplitude) 2. Intensity, I, is the rate of incidence of energy per unit area normal to the direction of incidence. The rate of incidence of energy can be regarded as power. The plane of the area, which the wave energy is incident onto, has to be normal (perpendicular) to the direction of the incidence of the wave energy. The unit of intensity is W m -2. Intensity on an area A can be expressed as I = P A where P is the power incident on the area normally. To help to recall Intensity (amplitude) 2 For rationale: From S.H.M., total energy can be expressed as mω x, where x o represents amplitude o So energy (amplitude) 2 Intensity (amplitude) 2. [Further information on Intensity can be found in the Extra Reading section] cfs / kpl Page 9 of 24
10 Example 5 A sound wave of amplitude 0.20 mm has an intensity of 3.0 W m -2. What will be the intensity of a sound wave of the same frequency which has an amplitude of 0.40 mm? Solution: The relation I (amplitude) 2 can be expressed as I = k(amplitude) 2 where k is the constant of proportionality. Substituting, 3.0 W m -2 = k(0.20 mm) (1) New intensity, I = k(0.40 mm) (2) (2) (1) : I = 4 I = 12.0 W m W m For sound waves, intensity is a measure of loudness. For light waves, intensity is a measure of brightness. r Example For a 40 W lamp, if the surface area of the light bulb is m 2, the intensity on the surface of the light bulb is 40/ W m -2 = 40 kw m -2. The bulb acts as a point source where light wave energy is propagated uniformly in all directions. bulb If the lamp has a transparent spherical shell of radius transparent spherical r enclosing the light bulb at its centre, the spherical shell surface area of the shell is 4πr 2. The intensity on the surface of the shell is the light power per unit area incident on the shell. Since it is not easy to determine the amount of light power incident on a unit area of the shell, it is not easy to determine the intensity on the shell surface by using the amount of power incident on unit area of the shell. For easy calculation, we consider all the power from the source to be incident on the whole area of the shell. The intensity at the surface of the shell, from a point source, can then be expressed as power of source I = 2 4π r 2 1 r cfs / kpl Page 10 of 24
11 Example 6 A point source of sound radiates energy uniformly in all directions. At a distance of 3.0 m from the source, the amplitude of vibration of air molecules is m. Assuming that no sound energy is absorbed, calculate the amplitude of vibration 5.0 m from the source. Solution: Using the relation above, 1 I r 2 and the relation I (amplitude) 2 we get the relation amplitude 1 r amplitude = c r where c is the constant of proportionality. Substituting, c m = 3.0 m c New amplitude = 5.0 m (1) (2) (2) (1) : New amplitude 3 = m 5 new amplitude = m. (f) Analyse and interpret graphical representations of transverse and longitudinal waves. In a wave, there are two directions of motions: (1) direction of propagation of energy (which is the direction of motion of the wave), (2) direction of oscillation of the particles in the wave. cfs / kpl Page 11 of 24
12 A transverse wave is one in which the direction of propagation of energy is perpendicular to the direction of oscillation of the particles in the wave. The string element s motion is perpendicular to the wave s direction of travel. This is a transverse wave. In the example of a wave travelling along a string (or a wave travelling along a slinky diagrams above, page 9), the direction of propagation of the wave is along the string. If the wave is started from one end of the string by the oscillation of the first element in the direction perpendicular to the string, then this wave travelling along the string is an example of a transverse wave. A longitudinal wave is one in which the direction of propagation of energy is parallel to the direction of oscillation of the particles in the wave. A visual demonstration of a longitudinal wave. When a sound wave set up by the vibrating piston propagates along the pipe of air, the direction of propagation of sound energy is along the pipe to the right. The direction of oscillation of the air layers is back and forth, parallel to this direction. Hence sound wave is an example of a longitudinal wave, as explained in the diagram below. A sound wave is set up in an air-filled pipe by moving a piston back and forth. The rightward motion of the piston moves the elements of air next to it rightward, changing the air pressure there. The increased air pressure then pushes rightward on the elements of air further along the pipe. Moving the piston leftward reduces the air pressure next to it. Hence the elements move backward and so forth. The motion of the air (and the change in air pressure) travel rightward along the pipe as a pulse. Since the motion of the elements of air is parallel to the direction of the wave s travel, it is a longitudinal wave. cfs / kpl Page 12 of 24
13 Graphs used to represent transverse or longitudinal waves are the same. Graph 1 : Displacement vs. Position graphs These are plotted with displacement, y, against distance or position, x. For a transverse wave moving from left to right along the x-axis, displacement of the particles in the wave, y, may be given a +ve sign for displacement upwards, and a ve sign for displacement downwards. For a longitudinal wave moving from left to right along the x-axis, displacement of the particles in the wave, y, may be given a +ve sign for displacement to the right, and a ve sign for displacement to the left. distance In Displacement vs. Position graphs, the graph represents the actual wave at an instant in time the distance between consecutive crests or consecutive troughs is one wavelength The maximum height of the vertical axis = amplitude of wave raph 2 : Displacement vs. Time graphs In contrast, graphs used to represent an oscillation of a particle are plotted with displacement, y, against time, t. In the graph above, we are tracking the displacement of one particle only as time goes by. This does NOT represent the wave. cfs / kpl Page 13 of 24
14 one period time In Displacement vs. Time graphs, The graph represents the oscillation of one particle on the wave with time. the distance between consecutive crests or consecutive troughs is one period The maximum height of the vertical axis = amplitude of oscillation Fig.2 shows 5 snapshots of a sinusoidal transverse wave in a string, travelling in the +ve direction of an x-axis (left to right). The movement of the wave is indicated by the right-ward progress of the short down-pointing arrow, pointing at the middle crest of the wave in snapshot (a). From snapshots (a) to (e), the short arrow moves to the right with the wave, but each particle in the string moves parallel to the y-axis (up and down). An example of such a particle is along the y-axis (shown darkened). Each snapshot is taken at an interval of ¼ period. One full oscillation takes place from (a) to (e). (e) Fig.2 cfs / kpl Page 14 of 24
15 In the 3 diagrams below (for longitudinal wave), diagram (1) shows the equilibrium positions of 15 particles and their displacements at a particular instant, (2) shows the corresponding displacement-distance graph (+ve displacement to the right), (3) shows the corresponding change in pressure for air layers in the atmosphere (for a sound wave travelling through air). Diagram (1) Actual positions of layers within the longitudinal wave Diagram (2) Displacement vs. Distance Diagram (3) Air Pressure vs. Distance cfs / kpl Page 15 of 24
16 Summary For Part (f): (1) Displacement-time graph is for the oscillation of a particle in the wave. The graph above shows an element oscillating with an amplitude of 4 mm. Its period of oscillation is about 5 ms. (2) Displacement-distance graph is for a snapshot of a wave motion at an instant. The graph above shows an instant of a wave with an amplitude of 4 mm. Its wavelength is about 1.8 m. E xample 7 The diagram below shows an instantaneous position of a string as a transverse progressive wave travels along it from left to right. Which one of the following correctly shows the directions of the velocities of the points 1, 2 and 3 on the string? Solution Knowing that the wave is traveling from LEFT to RIGHT, sketch how the wave would look like just an instant after: A B C D E Wave motion Then look at the points concerned. Since it is a TRANSVERSE wave, the particles only oscillates perpendicular to the wave direction. This eliminates Answers A & B. Ans : [ ] cfs / kpl Page 16 of 24
17 Example 8 The graph shows the shape at a particular instant of part of a transverse wave travelling along a string. Which statement about the motion of elements of the string is correct? A B C D The speed of the element at P is a maximum The displacement of the element at Q is always zero The energy of the element at R is entirely kinetic The acceleration of the element at S is a maximum Solution: Although the graph represents the whole wave at an instant in time, the question requires you to analyse the motion of the individual particles within the wave at this instant. Element P: At extreme end of oscillation stationary Element Q: At equilibrium position moving fastest Element R: At extreme end of oscillation stationary, no kinetic energy Element S: At extreme end of oscillation max displacement, max acceleration Ans: D (i) Show an understanding that polarisation is a phenomenon associated with transverse waves. Polarisation is a phenomenon in a transverse wave where the vibrations of the elements in the wave are restricted to a plane. Consider a transverse wave in a rope travelling along the x-direction: Transverse waves with initial oscillations in the y-direction cfs / kpl Page 17 of 24
18 Transverse waves initially oscillating (a) in the z-direction, and (b) at an angle in the y-z plane. In the cases above, the wave is plane-polarised ( i.e. the oscillations of the elements in the wave are in a plane). The following is adapted from Comprehensive Physics for A level (3 rd edition) Vol.2 KF Chan, Charles Chew, SH Chan (Federal Study Aids), page 32. In Figure 1, in a horizontal rope W Z, a transverse wave is set up by vibrations in many different planes by holding the end W, and moving it in all directions perpendicular to WZ, as illustrated by the arrows in plane P. 2 parallel slits X and Y are placed between W and Z. A wave then emerges along XY. Unlike the wave along WX (not shown) due to vibrations in different planes, the wave along XY is due only to vibrations parallel to slit X. This plane-polarised wave passes through the parallel slit Y. In Figure 2, the slit Y is turned such that it is perpendicular to slit X. No wave is observed beyond Y. To show that polarisation cannot be obtained with longitudinal waves, WZ is replaced by a thick elastic cord. Longitudinal waves can be produced along the cord, by vibrating the end W parallel to WZ. The longitudinal wave set up in cord WZ will pass through the slits X and Y when they are parallel (as in Fig.1) and when they are perpendicular (as in Fig.2). This shows that there is no polarisation. A longitudinal waves cannot be polarised because the particles in the wave oscillate parallel to the wave direction and cannot be restricted to vibrate in any plane. cfs / kpl Page 18 of 24
19 (h) Determine the frequency of sound using a calibrated c.r.o. A calibrated c.r.o. (cathode-ray oscilloscope) implies that the time-base is set such that the period, T, of oscillations of the air layers detected by the microphone may be read. Using the relation 1 f = T the frequency, f, of sound produced by the vibrating loudspeaker may be determined. Example 9 The trace shown appeared on an oscilloscope screen with the time-base set to 2.0 ms cm cm What is the frequency of the signal? A 40 Hz B 125 Hz C 250 Hz D 500 Hz Solution Period, T = 2.0 ms cm -1 4 cm = 8.0 ms Frequency, f = 1 T = 1 = 125 Hz s Ans: B (i) Determine the wavelength of sound using stationary waves. Please refer to notes on Stationary Waves in the topic Superposition. cfs / kpl Page 19 of 24
20 Extra Reading Electromagnetic Waves James Clerk Maxwell s ( ) crowning achievement was to show that a beam of light is a travelling wave of electric and magnetic field, an electro-magnetic wave. In Maxwell s time, the visible, infrared and ultraviolet form of light were the only electromagnetic waves known. Heinrich Hertz then discovered what we now call radio waves and verified that they move through the laboratory at the same speed as visible light. We now know a wide spectrum of electromagnetic waves. The Sun, being the dominant source of these waves, continually bathes us with electromagnetic waves throughout this spectrum. Type of EM wave Gamma (γ) rays x-rays UV ultraviolet Visible light IR (infra-red) Radio wave (includes microwaves, UHF, VHF etc) Typical Wavelengths λ and its corresponding frequency, f. λ = 1 pm = m f = 3 x Hz λ = 100 pm = m f = 3 x Hz λ = 10 nm = 10-8 m f = 3 x Hz λ red = 700 nm λ green = 600 nm = 0.6 μm λ violet = 400 nm f green = 5 x Hz λ = 100 μm = 10-4 m f = 3 x Hz λ = 3 m f = 10 8 Hz Orders of magnitude for wavelength, λ / m ~ 10-2 Properties of Electromagnetic Waves 1) EM waves have the same speed, c, in vacuum (c 3 x 10 8 m s -1 ). 2) EM waves consist of oscillating electric and magnetic fields that are perpendicular to each other. 3) EM waves are all transverse waves. cfs / kpl Page 20 of 24
21 Extra Reading Energy (E) and Intensity (I) of a Progressive Wave When we set up a wave on a stretched string, we provide energy for the motion of the string. As the wave moves away from us, it transports that energy as both kinetic energy and elastic potential energy. Kinetic Energy An element of the string of mass Δm, oscillating transversely in simple harmonic motion as the wave passes through it, has KE associated with its transverse velocity u. When the element is rushing through its y = 0 position (element b in the diagram), its transverse velocity and thus its KE - is a maximum. When the element is at its extreme position y = A (element a), its transverse velocity and thus its KE is zero. Elastic Potential Energy To send a sinusoidal wave along a previously straight string, the wave must necessarily stretch the string. As a string element of length Δx oscillates transversely, its length must increase and decrease in a periodic way if the string element is to fit the sinusoidal waveform. Elastic potential energy is associated with these length changes, just as for a spring. When the string element is at y = A, its length has its normal undisturbed value Δx, so its elastic potential energy is zero. However, when the element is rushing through its y = 0 position, it is stretched to its maximum extent, and its elastic potential energy then is a maximum. Energy Transmitted As waves travel through a medium, energy is transmitted as vibrational energy from particle to particle of the medium. The energy, E, is given by: Since E f 2 A 2 Intensity, I f 2 A 2. For a given source of fixed vibrations, f is constant. E f 2 A 2, where f = frequency, and A = amplitude where A = amplitude The unit for Intensity, I, is W m -2. I A 2 cfs / kpl Page 21 of 24
22 Polarisation of light Extra Reading The electromagnetic (E.M.) waves emitted by any common source of light (e.g. the Sun or a lamp) are polarized randomly or unpolarised; i.e., the electric field at any given point is always perpendicular to the direction of travel of the waves but changes direction randomly. Since E.M. waves are transverse in nature, they can be polarised. We can produce and detect polarised light by using polarising sheets, commercially known as Polaroids or Polaroid filters (invented by Edwin Land in 1932 while he was an undergraduate student). A polarising sheet consisits of certain long molecules embedded in plastic. When the sheet is manufactured, it is stretched to align the molecules in parallel rows. ELECTRIC FIELD MAGNETIC FIELD 3-D representation of an EM wave When light shines through a polariser, the electric field component parallel to the polarising direction passes through (transmitted); a component perpendicular to it is absorbed. Hence, the electric field of the light wave emerging from the sheet consists of only the componenets that are parallel to the polarising direction. Malus Law Taken from : Light travelling parallel to polariser the transmitted light has (almost) the same intensity as the polarised light (i.e. the amplitude of the light wave is identical). cfs / kpl Page 22 of 24
23 When the 2 nd polariser, or the Analyser is perpendicular to polariser, no transmitted light is observed. Hence, intensity is zero. (i.e. the amplitude of the light wave is zero). With the polariser and analyser at some other angle, θ, the amplitude of the transmitted light waves is equal to component of the amplitude of the polarised light parallel to the plane of the analyser. Therefore, amplitude of transmitted light is given by (amplitude of polarised light) cos θ Since intensity of a wave is proportional to its amplitude squared, we conclude that if polarised light is incident on a polarising filter, the intensity of the transmitted light is proportional to the cos 2 of the angle between the plane of polarisation and the plane of the filter: 2 I cos transmitted = I0 θ where I 0 is the intensity of the light incident on the analyser and I is the intensity of the transmitted light. This is called Malus law. U ses of Polarisers : LCD panels In LCD panels, a bright white light is emitted behind the panels. This source of light is typically a fluorescent backlight. In recent years, there has been a move to use LEDs to illuminate the panels leading to better energy efficiency. Liquid crystals are the 4 th state of matter, with plasma being the 5 th state. Liquid crystal is a liquid substance that has solid-like properties, often rod-shaped and their orientation can be changed using electric fields. The LCD panels is made from 2 polarizer with axis aligned 90 apart. Between these polarizer are 2 layers of glass panel, with an invisible electrode etched on each side. The electrodes are typically made of indium-tin-oxide, a transparent and conductive material. The liquid crystal is placed between these 2 glass panels, but their orientation gradually twists till they are 90 apart, each orientation corresponding to the polarizer s axis nearest to them. cfs / kpl Page 23 of 24
24 Diagram taken from : White light passing through the 1 st polarizer will be polarized in one direction, which then travels through the liquid crystals. The crystals change the plane of polarization, allowing light to be able to pass through the 2 nd polarizer. An observer will hence see that the screen is bright or white. When an electric field is applied across the liquid crystal, their crystal orientation is now straightened. Light passing the 1 st polarizer will hence travel along the liquid crystal but cannot pass through the 2 nd polarizer as it is 90 to it. An observer will observe the screen as dark or black. By controlling the electric field over very tiny areas (called pixels), light can be filtered out or allowed to pass through, creating an image on the screen. cfs / kpl Page 24 of 24
v = fλ PROGRESSIVE WAVES 1 Candidates should be able to :
PROGRESSIVE WAVES 1 Candidates should be able to : Describe and distinguish between progressive longitudinal and transverse waves. With the exception of electromagnetic waves, which do not need a material
More informationphysics 1/12/2016 Chapter 20 Lecture Chapter 20 Traveling Waves
Chapter 20 Lecture physics FOR SCIENTISTS AND ENGINEERS a strategic approach THIRD EDITION randall d. knight Chapter 20 Traveling Waves Chapter Goal: To learn the basic properties of traveling waves. Slide
More informationPhysical Science Study Guide Unit 7 Wave properties and behaviors, electromagnetic spectrum, Doppler Effect
Objectives: PS-7.1 Physical Science Study Guide Unit 7 Wave properties and behaviors, electromagnetic spectrum, Doppler Effect Illustrate ways that the energy of waves is transferred by interaction with
More information4.4 WAVE CHARACTERISTICS 4.5 WAVE PROPERTIES HW/Study Packet
4.4 WAVE CHARACTERISTICS 4.5 WAVE PROPERTIES HW/Study Packet Required: READ Hamper pp 115-134 SL/HL Supplemental: Cutnell and Johnson, pp 473-477, 507-513 Tsokos, pp 216-242 REMEMBER TO. Work through all
More informationWaves Sound and Light
Waves Sound and Light r2 c:\files\courses\1710\spr12\wavetrans.doc Ron Robertson The Nature of Waves Waves are a type of energy transmission that results from a periodic disturbance (vibration). They are
More informationCopyright 2008 Pearson Education, Inc., publishing as Pearson Addison-Wesley.
Chapter 20. Traveling Waves You may not realize it, but you are surrounded by waves. The waviness of a water wave is readily apparent, from the ripples on a pond to ocean waves large enough to surf. It
More informationAfter a wave passes through a medium, how does the position of that medium compare to its original position?
Light Waves Test Question Bank Standard/Advanced Name: Question 1 (1 point) The electromagnetic waves with the highest frequencies are called A. radio waves. B. gamma rays. C. X-rays. D. visible light.
More informationLesson 11. Luis Anchordoqui. Physics 168. Tuesday, December 8, 15
Lesson 11 Physics 168 1 Oscillations and Waves 2 Simple harmonic motion If an object vibrates or oscillates back and forth over same path each cycle taking same amount of time motion is called periodic
More information1) The time for one cycle of a periodic process is called the A) wavelength. B) period. C) frequency. D) amplitude.
practice wave test.. Name Use the text to make use of any equations you might need (e.g., to determine the velocity of waves in a given material) MULTIPLE CHOICE. Choose the one alternative that best completes
More informationWaves-Wave Characteristics
1. What is the wavelength of a 256-hertz sound wave in air at STP? 1. 1.17 10 6 m 2. 1.29 m 3. 0.773 m 4. 8.53 10-7 m 2. The graph below represents the relationship between wavelength and frequency of
More informationCurrent Staff Course Unit/ Length. Basic Outline/ Structure. Unit Objectives/ Big Ideas. Properties of Waves A simple wave has a PH: Sound and Light
Current Staff Course Unit/ Length August August September September October Unit Objectives/ Big Ideas Basic Outline/ Structure PS4- Types of Waves Because light can travel through space, it cannot be
More informationWaves - Transverse and Longitudinal Waves
Waves - Transverse and Longitudinal Waves wave may be defined as a periodic disturbance in a medium that carries energy from one point to another. ll waves require a source and a medium of propagation.
More informationPhysics 9e/Cutnell. correlated to the. College Board AP Physics 1 Course Objectives
Physics 9e/Cutnell correlated to the College Board AP Physics 1 Course Objectives Big Idea 1: Objects and systems have properties such as mass and charge. Systems may have internal structure. Enduring
More informationTennessee State University
Tennessee State University Dept. of Physics & Mathematics PHYS 2010 CF SU 2009 Name 30% Time is 2 hours. Cheating will give you an F-grade. Other instructions will be given in the Hall. MULTIPLE CHOICE.
More informationEnergy and Energy Transformations Test Review
Energy and Energy Transformations Test Review Completion: 1. Mass 13. Kinetic 2. Four 14. thermal 3. Kinetic 15. Thermal energy (heat) 4. Electromagnetic/Radiant 16. Thermal energy (heat) 5. Thermal 17.
More informationPHYS 222 Spring 2012 Final Exam. Closed books, notes, etc. No electronic device except a calculator.
PHYS 222 Spring 2012 Final Exam Closed books, notes, etc. No electronic device except a calculator. NAME: (all questions with equal weight) 1. If the distance between two point charges is tripled, the
More informationWaves and Sound. AP Physics B
Waves and Sound AP Physics B What is a wave A WAVE is a vibration or disturbance in space. A MEDIUM is the substance that all SOUND WAVES travel through and need to have in order to move. Two types of
More informationPHYA2. General Certificate of Education Advanced Subsidiary Examination June 2010. Mechanics, Materials and Waves
Centre Number Surname Candidate Number For Examiner s Use Other Names Candidate Signature Examiner s Initials Physics A Unit 2 For this paper you must have: a ruler a calculator a Data and Formulae Booklet.
More informationMAKING SENSE OF ENERGY Electromagnetic Waves
Adapted from State of Delaware TOE Unit MAKING SENSE OF ENERGY Electromagnetic Waves GOALS: In this Part of the unit you will Learn about electromagnetic waves, how they are grouped, and how each group
More informationExamples of Uniform EM Plane Waves
Examples of Uniform EM Plane Waves Outline Reminder of Wave Equation Reminder of Relation Between E & H Energy Transported by EM Waves (Poynting Vector) Examples of Energy Transport by EM Waves 1 Coupling
More informationThe University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICAL SETTING PHYSICS. Wednesday, June 17, 2015 1:15 to 4:15 p.m.
P.S./PHYSICS The University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICAL SETTING PHYSICS Wednesday, June 17, 2015 1:15 to 4:15 p.m., only The possession or use of any communications
More informationFriday 18 January 2013 Morning
Friday 18 January 2013 Morning AS GCE PHYSICS B (ADVANCING PHYSICS) G492/01 Understanding Processes / Experimentation and Data Handling *G411640113* Candidates answer on the Question Paper. OCR supplied
More informationCh 25 Chapter Review Q & A s
Ch 25 Chapter Review Q & A s a. a wiggle in time is called? b. a wiggle in space & time is called? a. vibration b. wave What is the period of a pendulum? The period is the time for 1 cycle (back & forth)
More informationEnergy. Mechanical Energy
Principles of Imaging Science I (RAD119) Electromagnetic Radiation Energy Definition of energy Ability to do work Physicist s definition of work Work = force x distance Force acting upon object over distance
More informationPHOTOELECTRIC EFFECT AND DUAL NATURE OF MATTER AND RADIATIONS
PHOTOELECTRIC EFFECT AND DUAL NATURE OF MATTER AND RADIATIONS 1. Photons 2. Photoelectric Effect 3. Experimental Set-up to study Photoelectric Effect 4. Effect of Intensity, Frequency, Potential on P.E.
More informationInfrared Spectroscopy: Theory
u Chapter 15 Infrared Spectroscopy: Theory An important tool of the organic chemist is Infrared Spectroscopy, or IR. IR spectra are acquired on a special instrument, called an IR spectrometer. IR is used
More informationPractice Test SHM with Answers
Practice Test SHM with Answers MPC 1) If we double the frequency of a system undergoing simple harmonic motion, which of the following statements about that system are true? (There could be more than one
More informationYerkes Summer Institute 2002
Before we begin our investigations into radio waves you should review the following material on your trip up to Yerkes. For some of you this will be a refresher, but others may want to spend more time
More informationInterference. Physics 102 Workshop #3. General Instructions
Interference Physics 102 Workshop #3 Name: Lab Partner(s): Instructor: Time of Workshop: General Instructions Workshop exercises are to be carried out in groups of three. One report per group is due by
More informationChapter 15, example problems:
Chapter, example problems: (.0) Ultrasound imaging. (Frequenc > 0,000 Hz) v = 00 m/s. λ 00 m/s /.0 mm =.0 0 6 Hz. (Smaller wave length implies larger frequenc, since their product,
More informationPHYS 101-4M, Fall 2005 Exam #3. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
PHYS 101-4M, Fall 2005 Exam #3 Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A bicycle wheel rotates uniformly through 2.0 revolutions in
More informationThe University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICAL SETTING PHYSICS. Friday, June 20, 2014 1:15 to 4:15 p.m.
P.S./PHYSICS The University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICAL SETTING PHYSICS Friday, June 20, 2014 1:15 to 4:15 p.m., only The possession or use of any communications device
More informationAP1 Waves. (A) frequency (B) wavelength (C) speed (D) intensity. Answer: (A) and (D) frequency and intensity.
1. A fire truck is moving at a fairly high speed, with its siren emitting sound at a specific pitch. As the fire truck recedes from you which of the following characteristics of the sound wave from the
More informationReview Vocabulary spectrum: a range of values or properties
Standards 7.3.19: Explain that human eyes respond to a narrow range of wavelengths of the electromagnetic spectrum. 7.3.20: Describe that something can be seen when light waves emitted or reflected by
More informationAcoustics: the study of sound waves
Acoustics: the study of sound waves Sound is the phenomenon we experience when our ears are excited by vibrations in the gas that surrounds us. As an object vibrates, it sets the surrounding air in motion,
More informationSample Questions for the AP Physics 1 Exam
Sample Questions for the AP Physics 1 Exam Sample Questions for the AP Physics 1 Exam Multiple-choice Questions Note: To simplify calculations, you may use g 5 10 m/s 2 in all problems. Directions: Each
More informationAZ State Standards. Concept 3: Conservation of Energy and Increase in Disorder Understand ways that energy is conserved, stored, and transferred.
Forms of Energy AZ State Standards Concept 3: Conservation of Energy and Increase in Disorder Understand ways that energy is conserved, stored, and transferred. PO 1. Describe the following ways in which
More informationAP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light
AP Physics B Ch. 23 and Ch. 24 Geometric Optics and Wave Nature of Light Name: Period: Date: MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Reflection,
More informationElectromagnetic (EM) waves. Electric and Magnetic Fields. L 30 Electricity and Magnetism [7] James Clerk Maxwell (1831-1879)
L 30 Electricity and Magnetism [7] ELECTROMAGNETIC WAVES Faraday laid the groundwork with his discovery of electromagnetic induction Maxwell added the last piece of the puzzle Heinrich Hertz made the experimental
More informationPhysics 202 Problems - Week 8 Worked Problems Chapter 25: 7, 23, 36, 62, 72
Physics 202 Problems - Week 8 Worked Problems Chapter 25: 7, 23, 36, 62, 72 Problem 25.7) A light beam traveling in the negative z direction has a magnetic field B = (2.32 10 9 T )ˆx + ( 4.02 10 9 T )ŷ
More informationHow To Understand Light And Color
PRACTICE EXAM IV P202 SPRING 2004 1. In two separate double slit experiments, an interference pattern is observed on a screen. In the first experiment, violet light (λ = 754 nm) is used and a second-order
More informationPhysics 25 Exam 3 November 3, 2009
1. A long, straight wire carries a current I. If the magnetic field at a distance d from the wire has magnitude B, what would be the the magnitude of the magnetic field at a distance d/3 from the wire,
More informationSpring Simple Harmonic Oscillator. Spring constant. Potential Energy stored in a Spring. Understanding oscillations. Understanding oscillations
Spring Simple Harmonic Oscillator Simple Harmonic Oscillations and Resonance We have an object attached to a spring. The object is on a horizontal frictionless surface. We move the object so the spring
More informationConceptual Physics Review (Chapters 25, 26, 27 & 28) Chapter 25 Describe the period of a pendulum. Describe the characteristics and properties of
Conceptual Physics Review (Chapters 25, 26, 27 & 28) Solutions Chapter 25 Describe the period of a pendulum. Describe the characteristics and properties of waves. Describe wave motion. Describe factors
More informationPhysics 121 Sample Common Exam 3 NOTE: ANSWERS ARE ON PAGE 6. Instructions: 1. In the formula F = qvxb:
Physics 121 Sample Common Exam 3 NOTE: ANSWERS ARE ON PAGE 6 Signature Name (Print): 4 Digit ID: Section: Instructions: Answer all questions 24 multiple choice questions. You may need to do some calculation.
More informationCambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level
Cambridge International Examinations Cambridge International Advanced Subsidiary and Advanced Level *0123456789* PHYSICS 9702/02 Paper 2 AS Level Structured Questions For Examination from 2016 SPECIMEN
More informationCandidate Number. General Certificate of Education Advanced Level Examination June 2014
entre Number andidate Number Surname Other Names andidate Signature General ertificate of Education dvanced Level Examination June 214 Physics PHY4/1 Unit 4 Fields and Further Mechanics Section Wednesday
More informationSTAAR Science Tutorial 30 TEK 8.8C: Electromagnetic Waves
Name: Teacher: Pd. Date: STAAR Science Tutorial 30 TEK 8.8C: Electromagnetic Waves TEK 8.8C: Explore how different wavelengths of the electromagnetic spectrum such as light and radio waves are used to
More informationUpon completion of this lab, the student will be able to:
1 Learning Outcomes EXPERIMENT B4: CHEMICAL EQUILIBRIUM Upon completion of this lab, the student will be able to: 1) Analyze the absorbance spectrum of a sample. 2) Calculate the equilibrium constant for
More informationWaves and Light Extra Study Questions
Waves and Light Extra Study Questions Short Answer 1. Determine the frequency for each of the following. (a) A bouncing spring completes 10 vibrations in 7.6 s. (b) An atom vibrates 2.5 10 10 times in
More informationPhysics 30 Worksheet # 14: Michelson Experiment
Physics 30 Worksheet # 14: Michelson Experiment 1. The speed of light found by a Michelson experiment was found to be 2.90 x 10 8 m/s. If the two hills were 20.0 km apart, what was the frequency of the
More informationName Date Class ELECTRONS IN ATOMS. Standard Curriculum Core content Extension topics
13 ELECTRONS IN ATOMS Conceptual Curriculum Concrete concepts More abstract concepts or math/problem-solving Standard Curriculum Core content Extension topics Honors Curriculum Core honors content Options
More informationG482 Electrons, Waves and Photons; Revision Notes Module 1: Electric Current
G482 Electrons, Waves and Photons; Revision Notes Module 1: Electric Current Electric Current A net flow of charged particles. Electrons in a metal Ions in an electrolyte Conventional Current A model used
More informationPhysics 6C, Summer 2006 Homework 2 Solutions
Physics 6C, Summer 006 Homework Solutions All problems are from the nd edition of Walker. Numerical values are different for each student. Chapter 3 Problems. Figure 3-30 below shows a circuit containing
More informationSimple Harmonic Motion(SHM) Period and Frequency. Period and Frequency. Cosines and Sines
Simple Harmonic Motion(SHM) Vibration (oscillation) Equilibrium position position of the natural length of a spring Amplitude maximum displacement Period and Frequency Period (T) Time for one complete
More informationQ1. The diagram below shows the range of wavelengths and frequencies for all the types of radiation in the electromagnetic spectrum.
Q. The diagram below shows the range of wavelengths and frequencies for all the types of radiation in the electromagnetic spectrum. X rays, which have frequencies in the range 0 8 0 2 Hz are already marked
More informationAP Physics C. Oscillations/SHM Review Packet
AP Physics C Oscillations/SHM Review Packet 1. A 0.5 kg mass on a spring has a displacement as a function of time given by the equation x(t) = 0.8Cos(πt). Find the following: a. The time for one complete
More informationScience In Action 8 Unit C - Light and Optical Systems. 1.1 The Challenge of light
1.1 The Challenge of light 1. Pythagoras' thoughts about light were proven wrong because it was impossible to see A. the light beams B. dark objects C. in the dark D. shiny objects 2. Sir Isaac Newton
More informationANALYSIS OF ASPIRIN INFRARED (IR) SPECTROSCOPY AND MELTING POINT DETERMINATION
Chem 306 Section (Circle) M Tu W Th Name Partners Date ANALYSIS OF ASPIRIN INFRARED (IR) SPECTROSCOPY AND MELTING POINT DETERMINATION Materials: prepared acetylsalicylic acid (aspirin), stockroom samples
More informationWeight The weight of an object is defined as the gravitational force acting on the object. Unit: Newton (N)
Gravitational Field A gravitational field as a region in which an object experiences a force due to gravitational attraction Gravitational Field Strength The gravitational field strength at a point in
More informationPLEASE DO NOT WRITE ON THE TEST. PLACE ALL MULTIPLE CHOICE ANSWERS ON THE SCANTRON. (THANK YOU FOR SAVING A TREE.)
PLEASE DO NOT WRITE ON THE TEST. PLACE ALL MULTIPLE CHOICE ANSWERS ON THE SCANTRON. (THANK YOU FOR SAVING A TREE.) Sound Waves Test -- each multiple choice question is worth 3 points. 1. Sound waves are
More informationChemistry 2 Chapter 13: Electrons in Atoms Please do not write on the test Use an answer sheet! 1 point/problem 45 points total
Chemistry 2 Chapter 13: Electrons in Atoms Please do not write on the test Use an answer sheet! 1 point/problem 45 points total 1. Calculate the energy in joules of a photon of red light that has a frequency
More informationUNIT 1: mechanical waves / sound
1. waves/intro 2. wave on a string 3. sound waves UNIT 1: mechanical waves / sound Chapter 16 in Cutnell, Johnson: Physics, 8th Edition Properties of waves, example of waves (sound. Light, seismic), Reflection,
More informationWaves: Recording Sound Waves and Sound Wave Interference (Teacher s Guide)
Waves: Recording Sound Waves and Sound Wave Interference (Teacher s Guide) OVERVIEW Students will measure a sound wave by placing the Ward s DataHub microphone near one tuning fork A440 (f=440hz). Then
More informationSOLUTIONS TO CONCEPTS CHAPTER 15
SOLUTIONS TO CONCEPTS CHAPTER 15 1. v = 40 cm/sec As velocity of a wave is constant location of maximum after 5 sec = 40 5 = 00 cm along negative x-axis. [(x / a) (t / T)]. Given y = Ae a) [A] = [M 0 L
More informationPhysics 1120: Simple Harmonic Motion Solutions
Questions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Physics 1120: Simple Harmonic Motion Solutions 1. A 1.75 kg particle moves as function of time as follows: x = 4cos(1.33t+π/5) where distance is measured
More informationA-level PHYSICS (7408/1)
SPECIMEN MATERIAL A-level PHYSICS (7408/1) Paper 1 Specimen 2014 Morning Time allowed: 2 hours Materials For this paper you must have: a pencil a ruler a calculator a data and formulae booklet. Instructions
More informationBlackbody Radiation References INTRODUCTION
Blackbody Radiation References 1) R.A. Serway, R.J. Beichner: Physics for Scientists and Engineers with Modern Physics, 5 th Edition, Vol. 2, Ch.40, Saunders College Publishing (A Division of Harcourt
More informationXX. Introductory Physics, High School
XX. Introductory Physics, High School High School Introductory Physics Test The spring 2013 high school Introductory Physics test was based on learning standards in the Physics content strand of the Massachusetts
More informationSound and stringed instruments
Sound and stringed instruments Lecture 14: Sound and strings Reminders/Updates: HW 6 due Monday, 10pm. Exam 2, a week today! 1 Sound so far: Sound is a pressure or density fluctuation carried (usually)
More information1. Units of a magnetic field might be: A. C m/s B. C s/m C. C/kg D. kg/c s E. N/C m ans: D
Chapter 28: MAGNETIC FIELDS 1 Units of a magnetic field might be: A C m/s B C s/m C C/kg D kg/c s E N/C m 2 In the formula F = q v B: A F must be perpendicular to v but not necessarily to B B F must be
More informationState Newton's second law of motion for a particle, defining carefully each term used.
5 Question 1. [Marks 20] An unmarked police car P is, travelling at the legal speed limit, v P, on a straight section of highway. At time t = 0, the police car is overtaken by a car C, which is speeding
More informationPreview of Period 3: Electromagnetic Waves Radiant Energy II
Preview of Period 3: Electromagnetic Waves Radiant Energy II 3.1 Radiant Energy from the Sun How is light reflected and transmitted? What is polarized light? 3.2 Energy Transfer with Radiant Energy How
More informationCandidate Number. General Certificate of Education Advanced Level Examination June 2012
entre Number andidate Number Surname Other Names andidate Signature General ertificate of Education dvanced Level Examination June 212 Physics PHY4/1 Unit 4 Fields and Further Mechanics Section Monday
More informationThe University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICAL SETTING PHYSICS. Thursday, June 13, 2013 1:15 to 4:15 p.m.
P.S./PHYSICS The University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICAL SETTING PHYSICS Thursday, June 13, 2013 1:15 to 4:15 p.m., only The possession or use of any communications
More informationCathode Ray Tube. Introduction. Functional principle
Introduction The Cathode Ray Tube or Braun s Tube was invented by the German physicist Karl Ferdinand Braun in 897 and is today used in computer monitors, TV sets and oscilloscope tubes. The path of the
More informationMagnetic Field and Magnetic Forces
Chapter 27 Magnetic Field and Magnetic Forces PowerPoint Lectures for University Physics, Thirteenth Edition Hugh D. Young and Roger A. Freedman Lectures by Wayne Anderson Goals for Chapter 27 Magnets
More informationLight as a Wave. The Nature of Light. EM Radiation Spectrum. EM Radiation Spectrum. Electromagnetic Radiation
The Nature of Light Light and other forms of radiation carry information to us from distance astronomical objects Visible light is a subset of a huge spectrum of electromagnetic radiation Maxwell pioneered
More informationCode number given on the right hand side of the question paper should be written on the title page of the answerbook by the candidate.
Series ONS SET-1 Roll No. Candiates must write code on the title page of the answer book Please check that this question paper contains 16 printed pages. Code number given on the right hand side of the
More informationCandidate Number. General Certificate of Education Advanced Level Examination June 2010
entre Number andidate Number Surname Other Names andidate Signature General ertificate of Education dvanced Level Examination June 1 Physics PHY4/1 Unit 4 Fields and Further Mechanics Section Friday 18
More informationExperiment 1: SOUND. The equation used to describe a simple sinusoidal function that propagates in space is given by Y = A o sin(k(x v t))
Experiment 1: SOUND Introduction Sound is classified under the topic of mechanical waves. A mechanical wave is a term which refers to a displacement of elements in a medium from their equilibrium state,
More informationPolarization of Light
Polarization of Light References Halliday/Resnick/Walker Fundamentals of Physics, Chapter 33, 7 th ed. Wiley 005 PASCO EX997A and EX999 guide sheets (written by Ann Hanks) weight Exercises and weights
More informationConceptual: 1, 3, 5, 6, 8, 16, 18, 19. Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65. Conceptual Questions
Conceptual: 1, 3, 5, 6, 8, 16, 18, 19 Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65 Conceptual Questions 1. The magnetic field cannot be described as the magnetic force per unit charge
More informationExperiment 5. Lasers and laser mode structure
Northeastern University, PHYS5318 Spring 2014, 1 1. Introduction Experiment 5. Lasers and laser mode structure The laser is a very important optical tool that has found widespread use in science and industry,
More informationAS COMPETITION PAPER 2008
AS COMPETITION PAPER 28 Name School Town & County Total Mark/5 Time Allowed: One hour Attempt as many questions as you can. Write your answers on this question paper. Marks allocated for each question
More informationWhat is Energy? What is the relationship between energy and work?
What is Energy? What is the relationship between energy and work? Compare kinetic and potential energy What are the different types of energy? What is energy? Energy is the ability to do work. Great, but
More informationLesson 3 DIRECT AND ALTERNATING CURRENTS. Task. The skills and knowledge taught in this lesson are common to all missile repairer tasks.
Lesson 3 DIRECT AND ALTERNATING CURRENTS Task. The skills and knowledge taught in this lesson are common to all missile repairer tasks. Objectives. When you have completed this lesson, you should be able
More informationPeriodic wave in spatial domain - length scale is wavelength Given symbol l y
1.4 Periodic Waves Often have situations where wave repeats at regular intervals Electromagnetic wave in optical fibre Sound from a guitar string. These regularly repeating waves are known as periodic
More informationPhysics 41 HW Set 1 Chapter 15
Physics 4 HW Set Chapter 5 Serway 8 th OC:, 4, 7 CQ: 4, 8 P: 4, 5, 8, 8, 0, 9,, 4, 9, 4, 5, 5 Discussion Problems:, 57, 59, 67, 74 OC CQ P: 4, 5, 8, 8, 0, 9,, 4, 9, 4, 5, 5 Discussion Problems:, 57, 59,
More informationANALYTICAL METHODS FOR ENGINEERS
UNIT 1: Unit code: QCF Level: 4 Credit value: 15 ANALYTICAL METHODS FOR ENGINEERS A/601/1401 OUTCOME - TRIGONOMETRIC METHODS TUTORIAL 1 SINUSOIDAL FUNCTION Be able to analyse and model engineering situations
More informationINTERFERENCE OF SOUND WAVES
1/2016 Sound 1/8 INTERFERENCE OF SOUND WAVES PURPOSE: To measure the wavelength, frequency, and propagation speed of ultrasonic sound waves and to observe interference phenomena with ultrasonic sound waves.
More informationCrystal Optics of Visible Light
Crystal Optics of Visible Light This can be a very helpful aspect of minerals in understanding the petrographic history of a rock. The manner by which light is transferred through a mineral is a means
More informationPHYSICS EXPERIMENTS (SOUND)
PHYSICS EXPERIMENTS (SOUND) In the matter of physics, the first lessons should contain nothing but what is experimental and interesting to see. A pretty experiment is in itself often more valuable than
More informationSimple Harmonic Motion
Simple Harmonic Motion 1 Object To determine the period of motion of objects that are executing simple harmonic motion and to check the theoretical prediction of such periods. 2 Apparatus Assorted weights
More informationD.S. Boyd School of Earth Sciences and Geography, Kingston University, U.K.
PHYSICAL BASIS OF REMOTE SENSING D.S. Boyd School of Earth Sciences and Geography, Kingston University, U.K. Keywords: Remote sensing, electromagnetic radiation, wavelengths, target, atmosphere, sensor,
More informationPractice final for Basic Physics spring 2005 answers on the last page Name: Date:
Practice final for Basic Physics spring 2005 answers on the last page Name: Date: 1. A 12 ohm resistor and a 24 ohm resistor are connected in series in a circuit with a 6.0 volt battery. Assuming negligible
More informationThe rate of change of velocity with respect to time. The average rate of change of distance/displacement with respect to time.
H2 PHYSICS DEFINITIONS LIST Scalar Vector Term Displacement, s Speed Velocity, v Acceleration, a Average speed/velocity Instantaneous Velocity Newton s First Law Newton s Second Law Newton s Third Law
More informationExperiment 8: Undriven & Driven RLC Circuits
Experiment 8: Undriven & Driven RLC Circuits Answer these questions on a separate sheet of paper and turn them in before the lab 1. RLC Circuits Consider the circuit at left, consisting of an AC function
More informationFrom lowest energy to highest energy, which of the following correctly orders the different categories of electromagnetic radiation?
From lowest energy to highest energy, which of the following correctly orders the different categories of electromagnetic radiation? From lowest energy to highest energy, which of the following correctly
More informationBoardworks AS Physics
Boardworks AS Physics Vectors 24 slides 11 Flash activities Prefixes, scalars and vectors Guide to the SI unit prefixes of orders of magnitude Matching powers of ten to their SI unit prefixes Guide to
More information