Chapter 13: Universal Gravitation


 Camilla Melton
 1 years ago
 Views:
Transcription
1
2 Chapter 13: Universal Gravitation I. The Falling Apple (13.1) A. Isaac Newton ( ) 1. Formulated ideas based on earlier work by Galileo (concept of inertia) 2. Concept if object undergoes change in speed or direction, then a force is responsible
3 B. Related falling apple, to the motion of the moon (falling around the earth)
4 II. The Falling Moon (13.2) A. Newton hypothesized that moon was simply a projectile circling Earth under the attraction of gravity 1. Newton had to test hypothesis 2. Compared fall of apple to fall of moon
5 3. Newton reasoned that gravitational attraction was diluted by distance a. Moon is 60 times farther from the center of the Earth than the apple b. Calculated difference to be 1/(60) 2
6 B. Newton waited 20 years to prove hypothesis 1. Invented a new math (Calculus) to explain theory 2. Published his findings The Law of Universal Gravitation. (applied to all objects in the universe)
7
8 III. The Falling Earth (13.3) A. Newton s theory confirmed Coperincan theory of the solar system. 1. Earth no longer considered center of universe 2. Earth not even center of solar system
9 B. Planets tangential velocities enough to keep in orbit
10 IV. Newton s Law of Universal Gravitation (13.4) A. Law states: every object attracts every other object with a force that for any two objects is directly proportional to the mass of each object 1. The greater the mass the greater the attraction 2. The farther away the objects are from each other, the less the force of attraction between them
11 B. Law expressed as: F m m 1 d 2 2 m 1 is mass of one object m 2 is mass of other d is distance between their centers
12 C. The Universal Gravitational Constant (G) 1. The above equation is a proportional form of law. 2. Can be expressed exactly when universal gravitational constant (G) is introduced a. Value of G first measured 150 years later by Henry Cavendish b. G X10 N m/ kg F G m m 1 d 2 2
13 3. Value of G tells us that force of gravity is a very weak force (weakest of known four fundamental forces (electromagnetic and two known nuclear forces
14 D. Cavendish used value of G to calculate the mass of the Earth (mass of Earth = 6 X kilograms)
15 V. Gravity and Distance: The Inverse Square Law (13.5) A.Inverse Square Law when quantity varies as the inverse square of its distance from its source B. Also applies to light, radiation, and sound
16
17 I. Gravitational Fields (13.6) A. Gravitational Field force field that surrounds massive objects B. Can be represented by imaginary field lines.
18 C. The strength of Earth s gravitational field is the force per unit mass exerted by Earth on any object. g F m 9.8 N kg 9.8 m s 2
19 D. The strength of its force on objects follows the inversesquare law (so g weakens with increasing distance from Earth
20 VII. Weight and Weightlessness (13.7) A. The force of gravity causes acceleration 1. Since we are almost always in contact with the Earth, we sense gravity as something that presses us against Earth rather than something that accelerates us 2. This pressing against Earth is what we interpret as weight
21 B. More practical to define weight as the force you exert against a supporting floor (or weighing scales) you are as heavy as you feel.
22 C. Weightlessness is not absence of gravity; rather, it is absence of a support force.
23
24 IX. Ocean Tides (13.9) A. Newton showed that the ocean tides are caused by differences in the gravitational pull of the moon on opposite sides of earth 1. Oceans bulge about 1 meter on opposite sides of Earth 2. Because Earth spins, the tides change as Earth rotates
25 B. Sun also contributes to tides 1. Sun s pull 180 times greater than moon, but contributes only half as much as the moon 2. Because difference in gravitational pullby sun on opposite sides of Earth very small (0.017% compared to 6.7% for moon's gravitation)
26 X. Black Holes (13.10) A. There are two main processes going on continuously in stars like our sun. 1. Process of Gravitation tends to crunch all solar material toward the center 2. Process of thermonuclear fusionconsisting of reactions similar to those in a hydrogen bomb. Tend to blow solar material outward
27 B. Two processes balance each other, resulting in given size for sun. 1. If fusion rate increases, the sun will get bigger and hotter. ( red giant ) 2. If fusion decreases, sun will get cooler and smaller. ( black dwarf )
28
29 C. Black Holes For very heavy stars (at least 2 or 3 times more massive than our sun), when flame of thermonuclear fusion is extinguished, gravitational collapse occurs
30 1.Star caves in on itself, with atoms also compress so that there is no empty spaces density becomes literally infinite 2. Gravitation near a black holes so great that nothing can get back out including light. 3. Although black holes can not be seen, their effects can be.
31 XI. Universal Gravitation (13.11) A. Law was used to explain perturbation of planets in our solar system 1. perturbationdeviations from normal orbits 2. Used law to explain Uranus s perturbation (caused by presence of another unknown planetneptune)
32 B. Theory dramatically affected science and society 1. Ushered in the Age of Reason or Century of Enlightenment. 2. Nurtured the thinking of scientists, artists, writers, and philosophers of the 1700 s
33 a. John Locke argued that observation and reason, as demonstrated by Newton, should be our best judge and guide in all things b. Locke and followers modeled system of government that culminated in the Declaration of Independence and Constitution of the United States of America
34 Einstein s Theory of Gravity Newton s theories did not explain the origin of gravity Einstein proposed gravity is not a force, but an effect of space itself. Einstein said a mass changes the space around it, causing space to be curved.
35 Called the General Theory of Relativity This theory provides accurate predictions of gravity s effects, but is still not complete. It does not explain how masses curve space
36 Assessment Questions 1. Newton determined that the pull of Earth s gravity caused both apples and a. the moon to fall toward Earth. b. the moon to move away from Earth. c. the sun to move away from Earth. d. stars to fall toward Earth.
37 Assessment Questions 1. Newton determined that the pull of Earth s gravity caused both apples and a. the moon to fall toward Earth. b. the moon to move away from Earth. c. the sun to move away from Earth. d. stars to fall toward Earth. Answer: A
38 Assessment Questions 2. The moon falls toward Earth in the sense that it falls a. with an acceleration of 10 m/s 2, as apples fall on Earth. b. with an acceleration greater than 10 m/s 2. c. beneath the straightline path it would take without gravity. d. above the straightline path it would take without gravity.
39 Assessment Questions 2. The moon falls toward Earth in the sense that it falls a. with an acceleration of 10 m/s 2, as apples fall on Earth. b. with an acceleration greater than 10 m/s 2. c. beneath the straightline path it would take without gravity. d. above the straightline path it would take without gravity. Answer: C
40 Assessment Questions 3. Planets remain in orbit while falling around the sun due to their a. tangential velocities. b. zero tangential velocities. c. accelerations of about 10 m/s 2. d. centrifugal forces that keep them up.
41 Assessment Questions 3. Planets remain in orbit while falling around the sun due to their a. tangential velocities. b. zero tangential velocities. c. accelerations of about 10 m/s 2. d. centrifugal forces that keep them up. Answer: A
42 Assessment Questions 4. Newton did not discover gravity, for early humans discovered it whenever they fell. What Newton did discover is that gravity a. tells us about why the universe expands. b. tells us how to discover new planets. c. accounts for the existence of black holes. d. extends throughout the universe.
43 Assessment Questions 4. Newton did not discover gravity, for early humans discovered it whenever they fell. What Newton did discover is that gravity a. tells us about why the universe expands. b. tells us how to discover new planets. c. accounts for the existence of black holes. d. extends throughout the universe. Answer: D
44 Assessment Questions 5. Consider a space probe three times as far from Earth s center. Compared at Earth s surface, its gravitational attraction to Earth at this distance is about a. one third as much. b. one half as much. c. one ninth as much. d. zero.
45 Assessment Questions 5. Consider a space probe three times as far from Earth s center. Compared at Earth s surface, its gravitational attraction to Earth at this distance is about a. one third as much. b. one half as much. c. one ninth as much. d. zero. Answer: C
46 Assessment Questions 6. Compared to the gravitational field of Earth at its surface, Earth s gravitational field at a distance three times as far from Earth s center is about a. one third as much. b. one half as much. c. one ninth as much. d. zero.
47 Assessment Questions 6. Compared to the gravitational field of Earth at its surface, Earth s gravitational field at a distance three times as far from Earth s center is about a. one third as much. b. one half as much. c. one ninth as much. d. zero. Answer: C
48 Assessment Questions 7. Compared to the gravitational field of Earth at its surface, Earth s gravitational field at Earth s center is a. zero. b. half as much. c. twice as much. d. three times as much.
49 Assessment Questions 7. Compared to the gravitational field of Earth at its surface, Earth s gravitational field at Earth s center is a. zero. b. half as much. c. twice as much. d. three times as much. Answer: A
50 Assessment Questions 8. When an astronaut in orbit is weightless, he or she is a. beyond the pull of Earth s gravity. b. still in the pull of Earth s gravity. c. in the pull of interstellar gravity. d. beyond the pull of the sun s gravity.
51 Assessment Questions 8. When an astronaut in orbit is weightless, he or she is a. beyond the pull of Earth s gravity. b. still in the pull of Earth s gravity. c. in the pull of interstellar gravity. d. beyond the pull of the sun s gravity. Answer: B
52 Assessment Questions 9. The highest ocean tides occur when the Earth and moon are a. lined up with the sun. b. at right angles to the sun. c. at any angle to the sun. d. lined up during spring.
53 Assessment Questions 9. The highest ocean tides occur when the Earth and moon are a. lined up with the sun. b. at right angles to the sun. c. at any angle to the sun. d. lined up during spring. Answer: A
54 Assessment Questions 10. A black hole is a. simply a collapsed star. b. a twodimensional surface in space. c. barely visible with highpowered telescopes. d. a new form of gravity.
55 Assessment Questions 10. A black hole is a. simply a collapsed star. b. a twodimensional surface in space. c. barely visible with highpowered telescopes. d. a new form of gravity. Answer: A
56 Assessment Questions 11. Newton s law of universal gravitation had a great impact on society as many scientists, artists, writers, and philosophers hoped that a. more complex and universal laws would explain other phenomena of the world. b. greater observations would require fewer experimentations. c. no further explanation of other phenomena of the world would be required. d. studying other phenomena of the world would lead to just as simple and universal laws.
57 Assessment Questions 11. Newton s law of universal gravitation had a great impact on society as many scientists, artists, writers, and philosophers hoped that a. more complex and universal laws would explain other phenomena of the world. b. greater observations would require fewer experimentations. c. no further explanation of other phenomena of the world would be required. d. studying other phenomena of the world would lead to just as simple and universal laws. Answer: D
58 Gravitation
59 1. Kepler s Laws a. Prior to Kepler  Aristotle s concept of an Earth centered system dominant thought until Copernicus develops heliocentric model b. Based on data gathered by Tycho Brahe  Danish astronomy somtimes referred to as the great observer. c. Based on the Conservation of Energy and Angular Momentum
60 d. Three Laws (1) Paths of planets are ellipses (nearly circular) with the sun at one focus Exaggerated the ellipse Sun
61 (2) Line from the sun to a planet sweeps out equal areas in equal amounts of time (a) At which point would have planet be moving faster? (b) Does this provide you with conservation of energy? Area 1 Area 2
62 (3) Ratio of the average radius (r) cubed to the period (T) squared is constant for all planets r 3 / T 2 = k r = average radius from planet to the sun T = period of revolution around the Why Average Radius? sun
63 2. Newton s Law of Universal Gravitation a. Every body attracts every other body with a force that varies based on the distance separating the bodies and their masses. F = G (M 1 M 2) / r 2 b. G is the universal gravitational constant  similar to a constant such as the speed of light, Avogadro s Number, etc G = 6.67 x Nm 2 /kg 2 or m 3 /kgsec 2
64 c. Developed by using Kepler s Third Law and equating force to centripetal force. r 3 / T 2 = k 1 implies T 2 = r 3 k 2 so if F c = m v 2 / r and v = 2 r / T then F c =[ m (2 r / T) 2 ] /r = m 4 2 r / T 2 F c = 4 2 r m / r 3 k 2 = k 3 m / r 2
65 d. Newton developed the concept but was not able to determine the value for G e. Value for G was found experimentally by Cavendish in 1798 (1) Led to the determination of the mass of the Earth (2) M E = 5.98 x kg
66 f. Gravitation  Distance and M 1 Mass Effects M 1 M 2 d M 2 d 2 M 1 M 2 M 1 M 1 2 d M 2 2 M 2 2 M 1 2 M 2 M 1 1/2 d M 2
67 g. Do Now Exercise Consider two satellites in orbit around a star (like our sun). If one satellite is twice as far from the star as the other, but both satellites are attracted to the star with the same gravitational force, how do the masses of the satellites compare? Sun
68 Answer If both satellites had the same mass, then the one twice as far would be attracted to the star with only onefourth the force (inverse square law). Since the force is the same for both, the mass of the farthermost satellite must be four times as great as the mass of the closer satellite.
69 h. If the sun suddenly collapsed to become a black hole, then the Earth would a. Leave the solar system in a straightline path. b. Spiral into the black hole c. Undergo a major increase in tidal forces d. Continue to circle in its usual orbit.?? Sun poof
70 We can see from Newton s Universal Law of Gravity equation, that the interaction F between the mass of the Earth and the Sun doesn t change. This is because the mass of the Earth does not change, the mass of the sun does not change even though it is compressed, and the distance from the centers of the Earth and the sun, collapsed or not, does not change. Although the Earth would very soon freezew and undergo enormous surface changes, its yearly path would continue
71 j. Extra Credit Group Problem A 50 kg astronaut is floating at rest in deep space 35 m from her stationary 150,000 kg spaceship. How long will it take her to float to the spaceship due to her attraction (gravity) with the ship? If she has a three hour supply of oxygen, will she make it to the ship in time? Help 35 meters
72 m = 50 kg r = 35 m M = 150,000 kg v 0 = 0 F = G (M 1 M 2) / r 2 = 4.08 x 107 N F = m a so a = F / m = 8.16 x 109 m/s 2 s = v 0 t + 1/2 a t 2 of oxygen t = 92, 600 sec runs out
73 k. Example Problem Compare the gravitational pull on a spaceship at the surface of the Earth with the gravitational pull when the ship is orbiting 1000 km above the surface. (r E = 6370 km) F = G (M 1 M 2) / r 2 25 % decrease. Note that the ship is still under effects of gravity and is NOT weightless.
74 3. Orbital Motion v  tangential velocity F  centripetal force v r  distance to center of mass of the Earth E r F c
75 a. Assume a circular orbit with gravity providing the centripetal Then force. F c mv 2 r F G GmM e r 2 which gives v GM e r b. Mass of the satellite is unimportant in describing its motion, only mass of planet.
76 c. We know that T 2 r v from v 2 r T so T 2 r 3 GM e d. Can be used for any body in orbit around another body.
77 e. Example Problems (1) A synchronous satellite will orbit at 3.6 x 10 7 m above the surface of the Earth. What is its speed? M e = 5.98x10 24 kg and r e = 6370 km. Givens: M e = v = 3068 m/s 5.98x10 24 kg r o = 36 x x 10 6 m G = 6.67 x Nm 2 /kg 2
78 (2) A moon of Jupiter, called Calisto, circles Jupiter each 16.8 days. Its orbital radius is 1.88 x 10 6 km. Find the mass of Jupiter. v 2 r T == v GM J r so that M J v 2 r G M J = 1.88 x kg
79 4. Law of Universal Gravitation and Weight a. Weight is due to gravity so w = G (M o M E) / r E 2 and since w = m g can determine g (acceleration due to gravity) g = G M E / r E 2 b. Weight changes with distance from the center of the Earth
80 c. Weight and Weightlessness (1). a GM e d 2 g changes with height and distance from center of the Earth (d) Therefore a g r e d 2 which allows you to calculate values for acceleration due to gravity for whatever distance you are above the Earth
81 (2) Weightlessness in space is not zero gravity, it is freefall. (a) Objects are still attracted by planet (b) Objects are falling toward the planet at the same rate the planet is falling away from them due to curvature of the planet s surface (c) Object still has weight in space
82 5. Gravitational Field a. First type of field force we have encountered. b. Use the concept of fields to explain how forces act through a distance, NOT WHY. c. Fields describe how forces act on an object due to its location.
83 d. Described using vectors and concentrations (1) The closer the lines are together the more powerfull is the field. (2) Direction of arrows shows the direction of attraction.
84 6. Two Kinds of Mass a. Inertial mass equal to the net force exerted on an object divided by the object s acceleration 2 nd Law b. Gravitational Mass from Newton s Law of Universal Gravitation attraction of one mass for another c. Principal of Equivalence proposes they are equal in magnitude.
85 7. Einstein a. Stated gravity is not a force, but an effect of space. b. Mass causes space to be curved, and this curving accounts for acceleration. c. Even light bends with gravity. d. Concept behind warp drive on Star Trek.
Name Class Date. true
Exercises 131 The Falling Apple (page 233) 1 Describe the legend of Newton s discovery that gravity extends throughout the universe According to legend, Newton saw an apple fall from a tree and realized
More information13 Universal Gravitation. Everything pulls on everything else.
Everything pulls on everything else. Gravity was not discovered by Isaac Newton. What Newton discovered, prompted by a falling apple, was that gravity is a universal force that it is not unique to Earth,
More informationGravity was not discovered by Isaac Newton. What Newton discovered, prompted by a falling apple, was that gravity is a. Everything pulls on
Everything pulls on everything else. Gravity was not discovered by Isaac Newton. What Newton discovered, prompted by a falling apple, was that gravity is a universal force that it is not unique to Earth,
More information4.1 Describing Motion. How do we describe motion? Chapter 4 Making Sense of the Universe: Understanding Motion, Energy, and Gravity
Chapter 4 Making Sense of the Universe: Understanding Motion, Energy, and Gravity 4.1 Describing Motion Our goals for learning:! How do we describe motion?! How is mass different from weight? How do we
More informationMr. Lin 1. 0 Universal Gravitation
0 Universal Gravitation a. Universal gravitation: Since the gravitational force is experienced by all matter in the universe, from the largest galaxies down to the smallest particles, it is often called
More informationMaking Sense of the Universe: Understanding Motion, Energy, and Gravity
Making Sense of the Universe: Understanding Motion, Energy, and Gravity 1. Newton s Laws 2. Conservation Laws Energy Angular momentum 3. Gravity Review from last time Ancient Greeks: Ptolemy; the geocentric
More informationName: Date: Period: Gravity Study Guide
Vocabulary: Define the following terms. Law of Universal Gravitation Gravity Study Guide Weight Weightlessness Gravitational Field Black hole Escape velocity Math: Be able to use the equation for the law
More informationThe Cosmic Perspective Seventh Edition. Making Sense of the Universe: Understanding Motion, Energy, and Gravity. Chapter 4 Lecture
Chapter 4 Lecture The Cosmic Perspective Seventh Edition Making Sense of the Universe: Understanding Motion, Energy, and Gravity Making Sense of the Universe: Understanding Motion, Energy, and Gravity
More information13 Universal Gravitation. Everything pulls on everything else.
Everything pulls on everything else. Gravity was not discovered by Isaac Newton. What Newton discovered, prompted by a falling apple, was that gravity is a universal force that it is not unique to Earth,
More informationToday: Chapter 9 (Gravity)
Today: Chapter 9 (Gravity) Chapter 9: Gravity Newton: made revolutionary connection between the circular motion of celestial bodies and the downward falling of objects on the earth: It is the one and the
More informationGravitation and Newton s Synthesis
Gravitation and Newton s Synthesis Vocabulary law of unviversal Kepler s laws of planetary perturbations casual laws gravitation motion casuality field graviational field inertial mass gravitational mass
More informationNewton s Law of Universal Gravitation
Newton s Law of Universal Gravitation The greatest moments in science are when two phenomena that were considered completely separate suddenly are seen as just two different versions of the same thing.
More informationUniversal Law of Gravitation Honors Physics
Universal Law of Gravitation Honors Physics Newton s Law of Universal Gravitation The greatest moments in science are when two phenomena that were considered completely separate suddenly are seen as just
More information7.2 Calculate force of gravity at a given distance given the force of gravity at another distance (making use of the inverse square relationship).
Chapter 7 Circular Motion and Gravitation 7.1 Calculate force of gravity using Newton s Law of Universal Gravitation. 5. What is the gravitational force between the Earth and the Sun? (Mass of Earth: 5.98
More informationChapter 4 Making Sense of the Universe: Understanding Motion, Energy, and Gravity
Chapter 4 Making Sense of the Universe: Understanding Motion, Energy, and Gravity How do we describe motion? Precise definitions to describe motion: Speed: Rate at which object moves sp e e d = d ista
More informationAST 101 Lecture 7. Newton s Laws and the Nature of Matter
AST 101 Lecture 7 Newton s Laws and the Nature of Matter The Nature of Matter Democritus (c. 470380 BCE) posited that matter was composed of atoms Atoms: particles that can not be further subdivided 4
More informationNewton s Universal Law of Gravitation The Apple and the Moon Video
Name Date Pd Newton s Universal Law of Gravitation The Apple and the Moon Video Objectives Recognize that a gravitational force exists between any two objects and that the force is directly proportional
More informationToday. Laws of Motion Conservation Laws Gravity tides. What is the phase of the moon?
Today Laws of Motion Conservation Laws Gravity tides What is the phase of the moon? How is mass different from weight? Mass the amount of matter in an object Weight the force that acts upon an object You
More information5. Universal Laws of Motion
5. Universal Laws of Motion If I have seen farther than others, it is because I have stood on the shoulders of giants. Sir Isaac Newton (1642 1727) Physicist 5.1 Describing Motion: Examples from Daily
More informationLesson 5 Rotational and Projectile Motion
Lesson 5 Rotational and Projectile Motion Introduction: Connecting Your Learning The previous lesson discussed momentum and energy. This lesson explores rotational and circular motion as well as the particular
More informationUnderstanding the motion of the Universe. Motion, Force, and Gravity
Understanding the motion of the Universe Motion, Force, and Gravity Laws of Motion Stationary objects do not begin moving on their own. In the same way, moving objects don t change their movement spontaneously.
More informationKepler, Newton and Gravitation
Kepler, Newton and Gravitation Kepler, Newton and Gravity 1 Using the unit of distance 1 AU = EarthSun distance PLANETS COPERNICUS MODERN Mercury 0.38 0.387 Venus 0.72 0.723 Earth 1.00 1.00 Mars 1.52
More informationChapter 3: Force and Motion
Force and Motion Cause and Effect Chapter 3 Chapter 3: Force and Motion Homework: All questions on the Multiple Choice and the oddnumbered questions on Exercises sections at the end of the chapter. In
More informationLecture 13. Gravity in the Solar System
Lecture 13 Gravity in the Solar System Guiding Questions 1. How was the heliocentric model established? What are monumental steps in the history of the heliocentric model? 2. How do Kepler s three laws
More informationtps Q: If the Earth were located at 0.5 AU instead of 1 AU, how would the Sun s gravitational force on Earth change?
tps Q: If the Earth were located at 0.5 AU instead of 1 AU, how would the Sun s gravitational force on Earth change? A. It would be onefourth as strong. B. It would be onehalf as strong. C. It would
More informationIntroduction to Gravity and Orbits. Isaac Newton. Newton s Laws of Motion
Introduction to Gravity and Orbits Isaac Newton Born in England in 1642 Invented calculus in early twenties Finally published work in gravity in 1687 The Principia Newton s Laws of Motion 1: An object
More informationMeasurements of Speed. Speed. v = d t. PowerPoint Lectures to accompany Physical Science, 6e
PowerPoint Lectures to accompany Physical Science, 6e Chapter 2 Motion Homework: All the multiple choice questions in Applying the Concepts and Group A questions in Parallel Exercises. Motion is.. A change
More informationClicker Question: Clicker Question: Gravitational Force. Newton's Law of Gravity. Inverse Square law Demo
Test results Last day to drop without a grade is Oct. 3 Grades posted in cabinet and online F D C B A A bullet is fired from a gun. Complete the following sentance to form a true statement. The speed of
More informationPHY1 Review for Exam 5
Topics 1. Uniform circular Motion a. Centripetal acceleration b. Centripetal force c. Horizontal motion d. ertical motion e. Circular motion with an angle 2. Universal gravitation a. Gravitational force
More informationUCMGravity. 2. The diagram shows two bowling balls, A and B, each having a mass of 7 kilograms, placed 2 meters apart.
1. A space probe is launched into space from Earth s surface. Which graph represents the relationship between the magnitude of the gravitational force exerted on Earth by the space probe and the distance
More informationUnification of the laws of the Earth and the Universe Why do planets appear to wander slowly across the sky?
October 19, 2015 Unification of the laws of the Earth and the Universe Why do planets appear to wander slowly across the sky? Key Words Newton s Laws of motion, and Newton s law of universal gravitation:
More informationLecture 5: Newton s Laws. Astronomy 111
Lecture 5: Newton s Laws Astronomy 111 Isaac Newton (16431727): English Discovered: three laws of motion, one law of universal gravitation. Newton s great book: Newton s laws are universal in scope,
More informationChapter 13 Newton s Theory of Gravity
Chapter 13 Newton s Theory of Gravity Chapter Goal: To use Newton s theory of gravity to understand the motion of satellites and planets. Slide 132 Chapter 13 Preview Slide 133 Chapter 13 Preview Slide
More informationQUESTION BANK UNIT6 CHAPTER8 GRAVITATION
QUESTION BANK UNIT6 CHAPTER8 GRAVITATION I. One mark Questions: 1. State Kepler s law of orbits. 2. State Kepler s law of areas. 3. State Kepler s law of periods. 4. Which physical quantity is conserved
More informationThe Main Point. The Scientific Method. Laws of Planetary Motion. Lecture #3: Orbits and Gravity. Laws of Planetary Motion:
Lecture #3: Orbits and Gravity Laws of Planetary Motion: Kepler's Laws. Newton's Laws. Gravity. Planetary Orbits. Spacecraft Orbits. The Main Point Motions of planets, moons, and asteroids can be very
More informationPractice Test (Chapter 10)
Practice Test (Chapter 10) 1) According to Kepler's laws, the paths of planets about the sun are A) parabolas. B) circles. C) straight lines. D) ellipses. Answer: D 2) Which of the following is not a vector
More informationUnderstanding the motion of the Universe. Motion, Force, and Gravity
Understanding the motion of the Universe Motion, Force, and Gravity Laws of Motion Stationary objects do not begin moving on their own. In the same way, moving objects don t change their movement spontaneously.
More informationNEWTON S LAWS OF MOTION
NEWTON S LAWS OF MOTION Background: Aristotle believed that the natural state of motion for objects on the earth was one of rest. In other words, objects needed a force to be kept in motion. Galileo studied
More informationKepler, Newton, and laws of motion
Kepler, Newton, and laws of motion !! " The only history in this course:!!!geocentric vs. heliocentric model (sec. 2.22.4)" The important historical progression is the following:!! Ptolemy (~140 AD) Copernicus
More informationLecture Outlines. Chapter 2. Astronomy Today 7th Edition Chaisson/McMillan Pearson Education, Inc.
Lecture Outlines Chapter 2 Astronomy Today 7th Edition Chaisson/McMillan Chapter 2 The Copernican Revolution Units of Chapter 2 2.1 Ancient Astronomy 2.2 The Geocentric Universe 2.3 The Heliocentric Model
More informationHow do we describe motion?
Lecture 3: The Laws of Motion and Universal Gravitation Astronomy 2020, Prof. Tom Megeath To be ignorant of motion is to be ignorant of nature Aristotle Overview of Today s Lecture 1. Newton s three laws
More informationAstron 100 Sample Exam 1 1. Solar eclipses occur only at (A) New moon (B) 1 st quarter moon (C) Full moon (D) 3 rd quarter moon (E) The equinoxes 2.
Astron 100 Sample Exam 1 1. Solar eclipses occur only at (A) New moon (B) 1 st quarter moon (C) Full moon (D) 3 rd quarter moon (E) The equinoxes 2. If the Moon is at first quarter tonight in Amherst,
More informationLecture 6: Newton & Kepler. Tycho Brahe ( ) Johannes Kepler
Lecture 6: Newton & Kepler Johannes Kepler (1600) was employed by Tycho to develop a mathematical theory to explain the observations made by Tycho Kepler was a pure theorist; Tycho a pure observer Issac
More informationGRAVITY CONCEPTS. Gravity is the universal force of attraction between all matter
IT S UNIVERSAL GRAVITY CONCEPTS Gravity is the universal force of attraction between all matter Weight is a measure of the gravitational force pulling objects toward Earth Objects seem weightless when
More informationQuestion on Class IX» Science» Gravitation» The Universal Law Of Gravitation.
Question on Class IX» Science» Gravitation» The Universal Law Of Gravitation. Q.1. When we move from the poles to the equator. Hence, the value of g decreases. Why Ans: The shape of earth is an ellipse
More informationNewton's Laws. Before Isaac Newton
Newton's Laws Before Isaac Newton Newton's Laws There were facts and laws about the way the physical world worked, but no explanations After Newton There was a unified system that explained those facts
More informationThe Motions of Celestial Bodies, and Newton s Laws of Motion
The Motions of Celestial Bodies, and Newton s Laws of Motion Announcements The results of Quiz 1 are posted in OWL Looking ahead: Homework 1 is ongoing, and is due on Thu, Sept. 29 th ; Homework 2 will
More informationGravity: The Law of Attraction
Gravity: The Law of Attraction 2009, Copyright@2008 Lecture 1, Oct. 1 2009 Oct. 1, 2009 #1 Questions of the day: How are Force, acceleration, and mass related? Why is gravity the most important force for
More informationAnnouncements. Eclipses 2/1/12. HW1 is due Thursday. You have to be registered at MasteringAstronomy to do the homework!
Announcements HW1 is due Thursday. You have to be registered at MasteringAstronomy to do the homework! TA Qufei Gu will be in RH111 4:005:00PM Wednesday to help with homework. Email: zyx88@unm.edu Feb
More informationSection Review Answers. Chapter 12
Section Review Answers Chapter 12 Section 1 1. Answers may vary. Students should say in their own words that an object at rest remains at rest and an object in motion maintains its velocity unless it experiences
More information1 Newton s Laws of Motion
Exam 1 Ast 4  Chapter 2  Newton s Laws Exam 1 is scheduled for the week of Feb 19th Bring Pencil Scantron 882E (available in the Bookstore) A scientific calculator (you will not be allowed to use you
More informationNotes: Most of the material in this chapter is taken from Young and Freedman, Chap. 13.
Chapter 5. Gravitation Notes: Most of the material in this chapter is taken from Young and Freedman, Chap. 13. 5.1 Newton s Law of Gravitation We have already studied the effects of gravity through the
More informationUnit 8 Lesson 2 Gravity and the Solar System
Unit 8 Lesson 2 Gravity and the Solar System Gravity What is gravity? Gravity is a force of attraction between objects that is due to their masses and the distances between them. Every object in the universe
More informationIs velocity constant? A = πr 2
Physics R Date: Circular Motion & Gravity Uniform Circular Motion What does uniform mean? Equations: (on reference table) Uniform circular motion means circular motion with C = 2πr = Is velocity constant?
More informationToday. Laws of Motion. Conservation Laws. Gravity
Today Laws of Motion Conservation Laws Gravity Laws of Motion Motion notions: slow fast Speed: Rate at which object moves fast change in direction slow example: speed of 10 m/s Velocity: Speed and direction
More informationGravitation. Physics 1425 Lecture 11. Michael Fowler, UVa
Gravitation Physics 1425 Lecture 11 Michael Fowler, UVa The Inverse Square Law Newton s idea: the centripetal force keeping the Moon circling the Earth is the same gravitational force that pulls us to
More informationConcept Review. Physics 1
Concept Review Physics 1 Speed and Velocity Speed is a measure of how much distance is covered divided by the time it takes. Sometimes it is referred to as the rate of motion. Common units for speed or
More informationName: Earth 110 Exploration of the Solar System Assignment 1: Celestial Motions and Forces Due in class Tuesday, Jan. 20, 2015
Name: Earth 110 Exploration of the Solar System Assignment 1: Celestial Motions and Forces Due in class Tuesday, Jan. 20, 2015 Why are celestial motions and forces important? They explain the world around
More informationDescribed by Isaac Newton
Described by Isaac Newton States observed relationships between motion and forces 3 statements cover aspects of motion for single objects and for objects interacting with another object An object at rest
More informationChapter 5: Circular Motion, the Planets, and Gravity
Chapter 5: Circular Motion, the Planets, and Gravity 1. Earth s gravity attracts a person with a force of 120 lbs. The force with which the Earth is attracted towards the person is A. Zero. B. Small but
More informationChapter 12  Forces and Motion
Chapter 12  Forces and Motion A. What is a force? 1. It is a push or pull. 2. Force can cause resting objects to move. 3. Force can cause acceleration by changing the object s speed or direction. 4. Newtons
More informationBlack holes 101(beyond science fiction)
Chapter 13: Gravitation Newton s Law of Gravitation Why is gravity important? Revisit the following: gravitational force, weight, and gravitational energy Stellar motions: the orbits of satellites and
More informationi>clicker Questions A scientific law is something that has been proven to be true. A. True B. False C. Only in experimental sciences.
A scientific law is something that has been proven to be true. A. True B. False C. Only in experimental sciences. i>clicker Questions The fifth planet from the sun, the sixth planet and the seventh planet
More informationForces. Isaac Newton was the first to discover that the laws that govern motions on the Earth also applied to celestial bodies.
Forces Now we will discuss the part of mechanics known as dynamics. We will introduce Newton s three laws of motion which are at the heart of classical mechanics. We must note that Newton s laws describe
More informationGravitation. Gravitation
1 Gravitation Newton s observations A constant center seeking force is required to keep an object moving along a circular path. You know that the moon orbits the earth and hence there should be a force
More informationUse the following information to deduce that the gravitational field strength at the surface of the Earth is approximately 10 N kg 1.
IB PHYSICS: Gravitational Forces Review 1. This question is about gravitation and ocean tides. (b) State Newton s law of universal gravitation. Use the following information to deduce that the gravitational
More informationExemplar Problems Physics
Chapter Eight GRAVITATION MCQ I 8.1 The earth is an approximate sphere. If the interior contained matter which is not of the same density everywhere, then on the surface of the earth, the acceleration
More informationPHY131H1F  Class 13. Today: Gravitational Potential Energy. Newton s Law of Universal Gravitation. The Gravitational Field.
PHY131H1F  Class 13 Today: Gravitational Potential Energy Newton s Law of Universal Gravitation The Gravitational Field Orbital Motion Two balls are launched along a pair of tracks with equal velocities,
More informationNewton s Law of Gravity and Kepler s Laws
Newton s Law of Gravity and Kepler s Laws Michael Fowler Phys 142E Lec 9 2/6/09. These notes are partly adapted from my Physics 152 lectures, where more mathematical details can be found. The Universal
More informationAstronomy 110 Homework #04 Assigned: 02/06/2007 Due: 02/13/2007. Name:
Astronomy 110 Homework #04 Assigned: 02/06/2007 Due: 02/13/2007 Name: Directions: Listed below are twenty (20) multiplechoice questions based on the material covered by the lectures this past week. Choose
More informationCentripetal Force. 1. Introduction
1. Introduction Centripetal Force When an object travels in a circle, even at constant speed, it is undergoing acceleration. In this case the acceleration acts not to increase or decrease the magnitude
More informationFrom Aristotle to Newton
From Aristotle to Newton The history of the Solar System (and the universe to some extent) from ancient Greek times through to the beginnings of modern physics. The Geocentric Model Ancient Greek astronomers
More informationHalliday, Resnick & Walker Chapter 13. Gravitation. Physics 1A PHYS1121 Professor Michael Burton
Halliday, Resnick & Walker Chapter 13 Gravitation Physics 1A PHYS1121 Professor Michael Burton II_A2: Planetary Orbits in the Solar System + Galaxy Interactions (You Tube) 21 seconds 131 Newton's Law
More information1 Kepler s Laws of Planetary Motion
1 Kepler s Laws of Planetary Motion 1.1 Introduction Johannes Kepler published three laws of planetary motion, the first two in 1609 and the third in 1619. The laws were made possible by planetary data
More informationHomework 4. problems: 5.61, 5.67, 6.63, 13.21
Homework 4 problems: 5.6, 5.67, 6.6,. Problem 5.6 An object of mass M is held in place by an applied force F. and a pulley system as shown in the figure. he pulleys are massless and frictionless. Find
More information356 CHAPTER 12 Bob Daemmrich
Standard 7.3.17: Investigate that an unbalanced force, acting on an object, changes its speed or path of motion or both, and know that if the force always acts toward the same center as the object moves,
More information12/3/10. Copyright 2008 Pearson Education, Inc., publishing as Pearson AddisonWesley.
The beautiful rings of Saturn consist of countless centimetersized ice crystals, all orbiting the planet under the influence of gravity. Chapter Goal: To use Newton s theory of gravity to understand the
More informationSummary: The Universe in 1650
Celestial Mechanics: The Why of Planetary Motions Attempts to Describe How Celestial Objects Move Aristotle, Hipparchus, and Ptolemy: The Ptolemaic System Aristarchus, Copernicus, and Kepler: The Copernican
More informationAP1 Gravity. at an altitude equal to twice the radius (R) of the planet. What is the satellite s speed assuming a perfectly circular orbit?
1. A satellite of mass m S orbits a planet of mass m P at an altitude equal to twice the radius (R) of the planet. What is the satellite s speed assuming a perfectly circular orbit? (A) v = Gm P R (C)
More informationPhysics Principles of Physics
Physics 140800 Principles of Physics Lecture 9 Chapter 6 February 5, 008 SungWon Lee Sungwon.Lee@ttu.edu Announcement I Lecture note is on the web Handout (4(or 6) slides/page) http://highenergy.phys.ttu.edu/~slee/1408/
More informationMotion and Gravity in Space
Motion and Gravity in Space Each planet spins on its axis. The spinning of a body, such a planet, on its axis is called rotation. The orbit is the path that a body follows as it travels around another
More informationNewton s Laws. Newton s Imaginary Cannon. Michael Fowler Physics 142E Lec 6 Jan 22, 2009
Newton s Laws Michael Fowler Physics 142E Lec 6 Jan 22, 2009 Newton s Imaginary Cannon Newton was familiar with Galileo s analysis of projectile motion, and decided to take it one step further. He imagined
More informationChapter 13. Gravitation
Chapter 13 Gravitation 13.2 Newton s Law of Gravitation In vector notation: Here m 1 and m 2 are the masses of the particles, r is the distance between them, and G is the gravitational constant. G = 6.67
More informationStudent Exploration: Gravitational Force
5. Drag STUDENT PACKET # 7 Name: Date: Student Exploration: Gravitational Force Big Idea 13: Forces and Changes in Motion Benchmark: SC.6.P.13.1 Investigate and describe types of forces including contact
More informationUniversal Gravitation Multiple Choice Homework
Universal Gravitation Multiple Choice Homework PSI Physics Name Multiple Choice Questions 1. The discovery of Universal Gravitation is associated with: A. Robert Hook B. Isaac Newton C. James Joule D.
More informationChapter 13 Newton s Theory of Gravity
Chapter 13 Newton s Theory of Gravity The textbook gives a good brief account of the period leading up to Newton s Theory of Gravity. I am not going to spend much time reviewing the history but will show
More informationPhysics Honors: Chapter 7 Practice Test
Physics Honors: Chapter 7 Practice Test Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. When an object is moving with uniform circular motion,
More informationHalliday, Resnick & Walker Chapter 13. Gravitation. Physics 1A PHYS1121 Professor Michael Burton
Halliday, Resnick & Walker Chapter 13 Gravitation Physics 1A PHYS1121 Professor Michael Burton II_A2: Planetary Orbits in the Solar System + Galaxy Interactions (You Tube) 21 seconds 131 Newton's Law
More informationcircular motion & gravitation physics 111N
circular motion & gravitation physics 111N uniform circular motion an object moving around a circle at a constant rate must have an acceleration always perpendicular to the velocity (else the speed would
More informationM OTION. Chapter2 OUTLINE GOALS
Chapter2 M OTION OUTLINE Describing Motion 2.1 Speed 2.2 Vectors 2.3 Acceleration 2.4 Distance, Time, and Acceleration Acceleration of Gravity 2.5 Free Fall 2.6 Air Resistence Force and Motion 2.7 First
More informationNewton, Einstein, and Gravity
Newton, Einstein, and Gravity I have not been able to discover the cause of those properties of gravity from phenomena, and I feign no hypotheses...and to us it is enough that gravity does really exist,
More informationPhysical Science Chapter 2. Forces
Physical Science Chapter 2 Forces The Nature of Force By definition, a Force is a push or a pull. A Push Or A Pull Just like Velocity & Acceleration Forces have both magnitude and direction components
More informationChapter 5. Determining Masses of Astronomical Objects
Chapter 5. Determining Masses of Astronomical Objects One of the most fundamental and important properties of an object is its mass. On Earth we can easily weigh objects, essentially measuring how much
More informationUniversity Physics 226N/231N Old Dominion University. Chapter 13: Gravity (and then some)
University Physics 226N/231N Old Dominion University Chapter 13: Gravity (and then some) Dr. Todd Satogata (ODU/Jefferson Lab) satogata@jlab.org http://www.toddsatogata.net/2016odu Monday, November 28,
More informationPhysics 130 Astronomy Exam #1 July 19, 2004
Physics 130 Astronomy Exam #1 July 19, 2004 Name Multiple Choice: 1. A scientist observes a new phenomenon that disagrees with his explanation or hypothesis. Following the scientific methods, he should
More informationASTR 1010 Astronomy of the Solar System Professor Caillault Fall 2009 Semester Exam 1 Answers
ASTR 1010 Astronomy of the Solar System Professor Caillault Fall 2009 Semester Exam 1 Answers 1. The number of degrees in a full circle is (c) 360 2. An arcsecond is a measure of (d) angle. 3. How many
More informationSatellites and Space Stations
Satellites and Space Stations A satellite is an object or a body that revolves around another object, which is usually much larger in mass. Natural satellites include the planets, which revolve around
More informationVersion A Page 1. 1. The diagram shows two bowling balls, A and B, each having a mass of 7.00 kilograms, placed 2.00 meters apart.
Physics Unit Exam, Kinematics 1. The diagram shows two bowling balls, A and B, each having a mass of 7.00 kilograms, placed 2.00 meters apart. What is the magnitude of the gravitational force exerted by
More informationName Class Period. F = G m 1 m 2 d 2. G =6.67 x 1011 Nm 2 /kg 2
Gravitational Forces 13.1 Newton s Law of Universal Gravity Newton discovered that gravity is universal. Everything pulls on everything else in the universe in a way that involves only mass and distance.
More informationNewton s Law of Gravity
Newton s Law of Gravity Example 4: What is this persons weight on Earth? Earth s mass = 5.98 10 24 kg Mar s mass = 6.4191 10 23 kg Mar s radius = 3400 km Earth s radius = 6378 km Newton s Form of Kepler
More information