LeaPS Workshop March 12, 2010 Morehead Conference Center Morehead, KY

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "LeaPS Workshop March 12, 2010 Morehead Conference Center Morehead, KY"

Transcription

1 LeaPS Workshop March 12, 2010 Morehead Conference Center Morehead, KY Word Bank: Acceleration, mass, inertia, weight, gravity, work, heat, kinetic energy, potential energy, closed systems, open systems, energy conservation, Newton s laws of motion. Learning targets:. I can show that forces come in pairs that are equal and opposite. I recognize that changing motion can be speeding up, slowing down, or changing direction. I can represent changes in motion using arrows. I can calculate acceleration from data about changes in motion over time. I can recognize that any change in motion is a consequence of unbalanced forces. I know that a change in motion (acceleration) is always in the direction of net force. I can show that acceleration is directly proportional to net force. I know that the mass of an object is related to its inertia, its tendancy to maintain its current state of motion. I know that the mass of an object is not the same as its weight; weight being the attraction between objects due to the force of gravity between them. I recognize the need to use low-friction objects to study the laws of motion. I can show that the acceleration of an object depends on both it mass and thenet force acting on it. I know that work performed on an object equals the force applied times its displacement. I recognize that work is a type of kinetic energy. I can calculate the kinetic energy of an object in motion knowing its mass and velocity. I can differentiate between open and closed systems with respect to energy transfers. I know that while energy is conserved in a closed system, it may be converted between kinetic energy, potential energy, or heat. 1

2 Newton s Third Law In our work in January, we found that forces always occur in pairs: You bumped hands with a groupmate. You felt a force in a direction toward you and your groupmate felt a force toward her. By measuring the size of these forces we would find that they are equal in size; they are clearly oppositely directed. Forces always occur between bodies and always occur in pairs, for example you are pushing on your groupmate and s/he is pushing on you. We cannot have one force without the other. This law of physics is stated as: In an interaction between body A and body B, body A exerts a force on body B and body B exerts an equal and opposite force on body A. These equal and opposite forces of an interaction never act on the same body, because an interaction is between bodies. This insight is not only a description of interactions but is also Newton s Third Law. You may have heard this stated (but less clearly so) as: To every action there is always an equal and opposite reaction. Consider a collision between two billiard balls: one moving directly at another one not initially moving. What happens with each ball? Does the moving ball change its motion? Does the stationary ball change its motion? Which one experiences a force? How do you know? What are the directions of all of the forces? How do you know? Observe the demonstration and discuss these questions in your group. When two magnets interact, one magnet experiences a force and the other magnet experiences an equal and opposite force. If one magnet is very large or heavy and the other is small or light, both magnets will experience the force equal and opposite, but the lighter one will respond more because it has less mass. 2

3 When a small car runs into a large truck, the force of the truck on the car is equal and opposite to the force of the car on the truck. The forces are equal and opposite, but the responses of the two bodies are different because the masses are different. Forces and changing motion From our work in February, we showed that changing motion can be described as changing velocity; continuously changing motion means continuously changing velocity. All changing motion involves changing velocity. If there is a changing velocity, there is a change in v, v, occurring as time passes along; after a very small time v(final) must be different from v(initial) v = v (final) v(initial) = v f v i I find it easier to think about rearranging and writing v f = v i + v. In other words, we need to add v to v i to get v f. There are three change-in-velocity scenarios to consider: when an object is speeding up, when it is slowing down, and when it is changing direction: For increasing v (speeding up) v i v f v When v is increasing, then v is in the same direction as v i, corresponding to a increase in v. For decreasing v (slowing down) v f v Note that the direction of v is opposite to that of v i and corresponds to a reduction of v: v f is less than that of v i v i For changing direction What is the v associated with changing direction? We know that we must have a v, 3

4 and v f = v i + v. When we change direction, the direction of the velocity changes and we velocity representations that look like this: v i v f v Note that if there is any v, then there must be a matching unbalanced force. In other words: unbalanced forces net force changing motion v Furthermore, the direction of the v is always in the same direction as the net force: v Net force As you suspected all along, any change in motion (speeding up, slowing down, or changing direction), is an acceleration. Changing motion is motion with a v, so acceleration is associated with v and in fact the definition of acceleration is: a = acceleration = v/ t, the change in velocity per unit of time Acceleration and v are always in the same direction. Whenever you want to know the direction of the acceleration, determine the v and you have it. The units of v and hence v are for most applications meters per second or m/s. Hence, the units for acceleration are meters per second x second or m/s 2. Now we can see that net force produces acceleration, following the logic unbalanced forces net force changing motion v a And just as with velocity, the direction of acceleration is the same as the direction of the net force. This connection between unbalanced forces and acceleration tells us that 4

5 NET FORCE IS PROPORTIONAL TO ACCELERATION If we are pushing on a body and increase net force then we get a larger acceleration. The symbol means proportional. Therefore, can write this proportionality as F(net) acceleration The net force and acceleration are directly proportional. Doubling the net force causes double the acceleration etc. We can write this in equation form including an as yet unspecified constant as How does mass fit into this? Motion and Inertia F(net) = (constant) acceleration or F(net) = (Constant)a The idea that a force is involved in motion is not terribly surprising. The value is in the details: an applied force causes acceleration (the continual change in motion of an object), the absence of a net force is necessary to maintain a constant speed, and deviance from these rules may be accounted for if we consider friction as a somewhat hidden force. The next topic we will deal with, the role of inertia, is at first glance, on the surface not tremendously shocking. Inertia refers to the tendency of an object to maintain its current state of motion. Therefore, an object at rest will remain at rest until put into motion by an applied force. A cart in motion will maintain its motion in a straight line unless a net force speeds it up, slows it down, or changes its direction. (This is called Newton s First Law of Motion.) As with the effect of force, the role or importance of inertia is in the details. In this section, you will investigate why some objects resist motion more than others, and how inertia can be incorporated into the general theory of motion. What characteristic of an object seems to determine how much force is needed to accelerate it? Imagine needing to accelerate two vehicles - a small car and a large truck (consider this under low-friction conditions). For which vehicle do you think it would be easier to change the speed continually from at-rest to a speed of 5

6 12mph with a given force the small car or the large truck? Discuss this in your groups. It is obvious to most people that if there is more stuff, then more force will be required to cause a continual change in speed. But suppose we double the amount of stuff. Will that mean that twice the net force is needed to accelerate double the stuff? Scientists have named the stuff about which we re talking mass. What Is Mass? Philosophers of science have great debates about the definition of mass. Many equate mass with weight, assuming that more stuff weighs more. While true on the surface of the earth, this is not true in outer space, where things become weightless. The weight of an object is due to the attraction its mass feels to other objects with mass. People have observed that one piece of mass attracts another piece of mass. Objects on earth have weight because their relatively small mass interacts with the mass of the earth and is attracted to the earth. We can call that pull its weight. In outer space, because things are not near an object with large mass such as the earth, they do not have this pull and hence do not have weight. The nuances of mass and weight are beyond the scope of our studies here, although you may wish to investigate this in another context. For now we will rely on our intuitive understanding of mass as some amount of stuff that affects how much an object resists changes in its motion. Mass measures inertia, the resistance to changes in motion a) Recall the experiments with the person on the skateboard. Suppose we had a volunteer that had much less mass than the original person. Imagine how the observations of the change would be different if we kept the pushing force the same. Note: We have to keep the pushing force the same!! Often we make assumptions about an experiment and lose track of what is being controlled. Here the pushing force needs to be kept constant; the experiment has no meaning if that is not the case. Suppose we had a volunteer who had much more mass than the original person. Imagine how the observation of the change in motion would be different if we kept the pushing force the same. Describe your ideas about the observed motion for original person on the cart, a much lighter person on the cart and a much heavier person on the cart always keeping the pushing force the same. 6

7 b) Think about a soccer ball being kicked so as to change its motion (slowing, speeding, changing direction). Suppose we replaced the soccer ball with a bowling ball. What do you think you would observe as a result of this increase in mass? Discuss this with your group, then observe the demonstration. [Group discussion about the effect of mass just observed] What do you think you would observe about changes in the motion of a low friction cart if we added weights with about the same amount of stuff (mass) as the cart itself? We will do this activity by approximately doubling the amount of stuff compared to the plain cart. You may note that the cart with more mass may be pushing down harder on the table and maybe have a higher friction force. This would be true for objects with measurable friction, like the person on the blanket, however with good low friction devices, the friction remains essentially zero for all reasonable added masses. In reality, the friction is never zero but for all practical purposes it can be ignored. If we apply the same net force for both, how would the motion of the friction-free cart with about double the stuff compare with that of cart alone? We will do the experiment with the cart mass alone, more mass and cart, and finally even more mass and cart and do it with a medium force and a large force. For the activities in this section each group will need: 1 spring scale like we used before 1 low friction cart or 4 inch car on which we can place additional mass like we used previously Weights for increasing mass, each block should have about the same mass as the car/truck so that adding one doubles mass and adding two triples the mass LabQuests (LQ), fully charged You will need to investigate how to interpret LabQuest velocity data. In this experiment, you will be applying a constant force and observing a change in velocity. Based on the earlier discussion about acceleration, you can take the change in velocity and divide it by the time interval during that velocity change to calculate the acceleration. Discuss in your group exactly what data is needed. Then try it a few times to get the sense of how to do it efficiently. Check with facilitators that you are carrying out this operation correctly. At first, try this activity without using the LQ, just to get a feel of what is going on. With no added weights pull the cart or block with a medium force and observe 7

8 the change in motion qualitatively. Record your feel for it such as: slowly increasing in velocity or rapidly increasing in velocity, remembering that you want to keep force constant. Then add weights equal to the mass of the cart and repeat the experiment with the same medium force. Then add additional weights and repeat with the same medium force. As mass is increased is the change in motion greater or lesser? Record your observations in writing here and in the table below. Now do the same set of experiments except exert a larger force with the springscale, keeping the force equal for the different masses. Record your results in writing here and in the table below. Is the change in motion for the higher force greater, lesser or the same as that for the medium force for all three cases? You may need to repeat some of your medium force experiments to make the comparisons. Complete the following chart as a way of summarizing your observations: Table for Cart Experiments, circle appropriate term or make entry Cart mass Medium force exerted Larger force exerted No added weights Change in motion is: very small, small, moderate, large, very large Change in motion is: very small, small, moderate, large, very large Double mass Triple mass Change in motion is: very small, small, moderate, large, very large Change in motion is: very small, small, moderate, large, very large Change in motion is: very small, small, moderate, large, very large Change in motion is: very small, small, moderate, large, very large Next, carry out these activities in a quantitative manner using the LabQuests. CHECK write down your conclusions from this activity as to how changing mass affects the ability of a constant net force to change motion in a straight line. Share your conclusions with a facilitator. Most people observe that as mass increases, for the same net force the change in motion is less; conversely as the mass is decreased for the same net force applied to the body the change of motion is greater. Do your observations agree with this? Do you believe this? 8

9 There are two linked observations here critical to understanding the laws of motion: You have verified the law of proportionality between the applied force and the resulting speeding up. Acceleration is directly proportional to the applied force; that is, the acceleration doubles when the applied force doubles. The acceleration also depends upon the mass of the carts, however. When there is twice as much mass, the acceleration is halved. We say that acceleration is inversely proportional to the mass, when a constant net force is applied. The data you collected imply a mathematical relationship among net force, mass, and acceleration. These parameters can be combined in an equation form like this: acceleration Net F/m where net F is the net force and m is the mass. Note this equation tells us that for a larger m while keeping the net F constant, the acceleration is less. For a larger net force while keeping the mass constant results in an acceleration that is larger. With units of kilograms for mass, newtons for force and meters per second 2 for acceleration, we can write this equation as a = net F/m or if we multiply both of the equation by m we get net F = ma. net F = ma Congratulations! Through a study of motion, you have uncovered Newton s Second Law, which essentially says that the changing motion, or acceleration, of an object depends directly on the net force applied to it and inversely on how massive the object is. That it took over 2000 years of research and the development of calculus to derive these laws should give you an idea of exactly how difficult these understandings are. And yet you did it in just a morning s worth of work! Congratulations!!!!!!!!!!, but we are not through. 9

10 Work and Heat Mechanical work is defined in terms of force and the displacement through which the force acts. When the direction of the force and the direction of the displacement are the same the relationship is Work = (Force)x(displacement) often written as (Force)(distance) or Fd. Force direction (F) Distance (d) W = Fd, when force and displacement in same direction. Note that when the force and displacement are not in the same direction, the equation for calculating the work is a little more complicated. We will not work with these cases, so we are limited to studying situations where the force and displacement are in the same direction. Think back to one of our first experiments pushing a person on the skateboard. We applied a force of about 40 pounds as measured by our weight scale. If we had used a scale calibrated in newtons (N) we would have had 178 N where the conversion is 1 pound = 4.45 newtons. (40 pounds)x(4.45newtons/pound) = 178 newtons Notice the unit pounds cancels out in the equation (40 pounds)x(4.45newtons/pound) = 178 newtons Kinetic energy (KE) is the energy associated with motion and it can be calculated with the defining equation Kinetic energy =KE= 1/2 m v 2, where KE is measured in joules, m is mass in kilograms and v is the speed in meters per second. The most basic statement about energy in mechanics is that The work done by all forces on an object is equal to the CHANGE in kinetic energy of the object. For our pushing on the friction-free skateboard the forces add to form the net force; in our case the net force is equal to the force of our push since there is essentially no friction force (and there are no unbalanced forces in the vertical direction). 10

11 Calculate the work done when we pushed the person a displacement of 1 meter. The units in your answer will be newton x meter or newton meter. One newton meter is equal to a joule. As you may recall we stopped taking data when we had pushed the person 747 cm or 7.47 m. Calculate the work done by the pushing force when we pushed the person 7.47 meters. Discuss the following in your group: If the net force on an object is zero, because all the forces are balanced and there is no change in motion, what total work is done? What change in velocity would you expect? What change in kinetic energy would you expect? Does this agree with what you would expect using Newton's Second Law? When the total or net work done on an object is zero, is the kinetic energy of that object conserved, i.e. does it remain constant? Energy Transformations The problem just completed is a simple example of energy conservation. In this case kinetic energy is conserved because the final kinetic energy is equal to the initial kinetic energy. If you studied heat you know that it is energy in transit. Heat is energy that transfers from a hotter (higher temperature) body to a colder body. If a heating experiment is done in an insulated container, all the energy that leaves the hotter body goes to the colder body and energy in the insulated container is conserved. One can keep track of the heating and cooling and confirm this. You have likely thought about other forms of energy like chemical energy, light energy etc. The principle of energy conservation can be extended to many other cases, although we will not prove or demonstrate it here. For example, if an object like a 1 kg block of wood is sliding on a table with a speed of 2 m/s it has kinetic energy in an amount that you can calculate. Discuss what you think happens to this kinetic energy as the block slides to a stop. There are many applications of the energy conservation principle throughout physics and all of science. It is one of the cornerstones of our scientific view of the world. If there are no external sources or losses of energy from a system, when all forms of energy are considered for the system, the total energy of the system remains constant. We call a system for which energy does not go out or in and is only transformed within and transferred between things in the system, a CLOSED or ISOLATED SYSTEM. Energy can change forms, but the total amount of energy in a closed system remains constant 11

12 What is potential energy? Here are some basic definitions, phrased informally: Kinetic energy = The energy something has because of its motion. The heavier or faster something is, the more kinetic energy it has. Gravitational potential energy = The energy stored in an object because it s been lifted. The energy is potential because it has the potential to turn into kinetic energy for instance, if the object gets dropped. The heavier or higher an object is, the more potential energy is stored up. There are other types of potential energy as well such as chemical energy. Consider and discuss the following scenario: A child pushes a loaded wagon up a hill, starting slowly but gradually getting faster and faster. Is the wagon gaining kinetic energy, gravitational potential energy, both, or neither? Explain. Suppose the wagon gains a total of 50 joules of energy. According to energy conservation, energy is never created nor destroyed. But the wagon just gained 50 joules! What is meant by this statement? Does this scenario contradict conservation of energy? Explain why or why not. When you say something like a jogger just burned 100 calories of energy, what does that mean? Where exactly do those 100 calories come from? In other words, what form of energy is depleted by 100 calories? Hint: This is as much a biology or chemistry question as it is a physics question. Roughly speaking, when work is done on a body, the mechanical energy the kinetic and potential energy are changed an amount equal to the work done. How much work did the child do on the wagon? CHECK Make sure that you have written full responses to all the questions and discussed your ideas with your groupmates before doing the check. Lifting Objects; Work Done In this problem, you ll use the formal definition of work to figure out some stuff. Recall W = Fd, with force and displacement in the same direction. A student holds a book of mass m in her hand and raises the book vertically at constant speed. Make a drawing to illustrate the motion of the book, showing its position at regular time intervals; this diagram is sometimes called a Motion diagram, especially if the 12

13 positions at equally separated times are shown. For example, an object moving at a constant speed could be represented with dots at equally spaced times. Suppose the student does 25 joules of work lifting the book. 1. Does the book (lifted at constant speed) gain potential energy, kinetic energy, or both? Explain. 2. Is the potential energy gained by the book greater than, less than, or equal to 25 joules? Explain. Check. Make sure that you have written full responses to all the questions and discussed your ideas with your groupmates before doing the check. Pushing on a wall In this section we ll clarify the meaning of work. A student pushes hard enough on a wall that she breaks a sweat. The wall, however, does not move. Does the student do any work on the wall? Answer using: a. your intuition b. work as defined above Apparently, some reconciliation is needed. We ll lead you through it. In this scenario, does the student give the wall any energy? Does the student expend energy (i.e., use up chemical energy stored in her body)? If the energy spent by the student doesn t go into the wall s mechanical energy, where does it go? Is it just gone, or is it transformed into something else? Hint: How do you feel when you ve expended lots of energy? Intuitively, when you push on a wall, are you doing useful work or are you wasting energy? 13

14 A student says, In everyday life, doing work means the same thing as expending energy. But in physics, work corresponds more closely to the intuitive idea of useful work, work that accomplishes something, as opposed to just wasting energy. That s why it s possible to expend energy without doing work in the physics sense. In what ways do you agree or disagree with the student s analysis? Let s check for consistency between intuition and definitions. Does the student s idea that doing work means expending energy mesh with the rough definition of work as the mechanical (kinetic and potential) energy given to something? Check. Make sure that you have written full responses to all the questions and discussed your ideas with your groupmates before doing the check. 14

NEWTON S LAWS OF MOTION

NEWTON S LAWS OF MOTION Name Period Date NEWTON S LAWS OF MOTION If I am anything, which I highly doubt, I have made myself so by hard work. Isaac Newton Goals: 1. Students will use conceptual and mathematical models to predict

More information

4 Gravity: A Force of Attraction

4 Gravity: A Force of Attraction CHAPTER 1 SECTION Matter in Motion 4 Gravity: A Force of Attraction BEFORE YOU READ After you read this section, you should be able to answer these questions: What is gravity? How are weight and mass different?

More information

Physics 11 Assignment KEY Dynamics Chapters 4 & 5

Physics 11 Assignment KEY Dynamics Chapters 4 & 5 Physics Assignment KEY Dynamics Chapters 4 & 5 ote: for all dynamics problem-solving questions, draw appropriate free body diagrams and use the aforementioned problem-solving method.. Define the following

More information

Chapter 7: Momentum and Impulse

Chapter 7: Momentum and Impulse Chapter 7: Momentum and Impulse 1. When a baseball bat hits the ball, the impulse delivered to the ball is increased by A. follow through on the swing. B. rapidly stopping the bat after impact. C. letting

More information

ACTIVITY 6: Falling Objects

ACTIVITY 6: Falling Objects UNIT FM Developing Ideas ACTIVITY 6: Falling Objects Purpose and Key Question You developed your ideas about how the motion of an object is related to the forces acting on it using objects that move horizontally.

More information

Chapter 4: Newton s Laws: Explaining Motion

Chapter 4: Newton s Laws: Explaining Motion Chapter 4: Newton s Laws: Explaining Motion 1. All except one of the following require the application of a net force. Which one is the exception? A. to change an object from a state of rest to a state

More information

Name Partners Date. Energy Diagrams I

Name Partners Date. Energy Diagrams I Name Partners Date Visual Quantum Mechanics The Next Generation Energy Diagrams I Goal Changes in energy are a good way to describe an object s motion. Here you will construct energy diagrams for a toy

More information

LAB 6: GRAVITATIONAL AND PASSIVE FORCES

LAB 6: GRAVITATIONAL AND PASSIVE FORCES 55 Name Date Partners LAB 6: GRAVITATIONAL AND PASSIVE FORCES And thus Nature will be very conformable to herself and very simple, performing all the great Motions of the heavenly Bodies by the attraction

More information

v v ax v a x a v a v = = = Since F = ma, it follows that a = F/m. The mass of the arrow is unchanged, and ( )

v v ax v a x a v a v = = = Since F = ma, it follows that a = F/m. The mass of the arrow is unchanged, and ( ) Week 3 homework IMPORTANT NOTE ABOUT WEBASSIGN: In the WebAssign versions of these problems, various details have been changed, so that the answers will come out differently. The method to find the solution

More information

Newton s Laws of Motion

Newton s Laws of Motion Newton s Laws of Motion The Earth revolves around the sun in an elliptical orbit. The moon orbits the Earth in the same way. But what keeps the Earth and the moon in orbit? Why don t they just fly off

More information

9. The kinetic energy of the moving object is (1) 5 J (3) 15 J (2) 10 J (4) 50 J

9. The kinetic energy of the moving object is (1) 5 J (3) 15 J (2) 10 J (4) 50 J 1. If the kinetic energy of an object is 16 joules when its speed is 4.0 meters per second, then the mass of the objects is (1) 0.5 kg (3) 8.0 kg (2) 2.0 kg (4) 19.6 kg Base your answers to questions 9

More information

5. Forces and Motion-I. Force is an interaction that causes the acceleration of a body. A vector quantity.

5. Forces and Motion-I. Force is an interaction that causes the acceleration of a body. A vector quantity. 5. Forces and Motion-I 1 Force is an interaction that causes the acceleration of a body. A vector quantity. Newton's First Law: Consider a body on which no net force acts. If the body is at rest, it will

More information

9. Momentum and Collisions in One Dimension*

9. Momentum and Collisions in One Dimension* 9. Momentum and Collisions in One Dimension* The motion of objects in collision is difficult to analyze with force concepts or conservation of energy alone. When two objects collide, Newton s third law

More information

Review Vocabulary force: a push or a pull. Vocabulary Newton s third law of motion

Review Vocabulary force: a push or a pull. Vocabulary Newton s third law of motion 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 information

LAB 6 - GRAVITATIONAL AND PASSIVE FORCES

LAB 6 - GRAVITATIONAL AND PASSIVE FORCES L06-1 Name Date Partners LAB 6 - GRAVITATIONAL AND PASSIVE FORCES OBJECTIVES And thus Nature will be very conformable to herself and very simple, performing all the great Motions of the heavenly Bodies

More information

Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion

Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion Conceptual Questions 1) Which of Newton's laws best explains why motorists should buckle-up? A) the first law

More information

Chapter 6. Work and Energy

Chapter 6. Work and Energy Chapter 6 Work and Energy ENERGY IS THE ABILITY TO DO WORK = TO APPLY A FORCE OVER A DISTANCE= Example: push over a distance, pull over a distance. Mechanical energy comes into 2 forms: Kinetic energy

More information

Newton s Laws. Physics 1425 lecture 6. Michael Fowler, UVa.

Newton s Laws. Physics 1425 lecture 6. Michael Fowler, UVa. Newton s Laws Physics 1425 lecture 6 Michael Fowler, UVa. Newton Extended Galileo s Picture of Galileo said: Motion to Include Forces Natural horizontal motion is at constant velocity unless a force acts:

More information

Newton s Laws. Newton s Imaginary Cannon. Michael Fowler Physics 142E Lec 6 Jan 22, 2009

Newton 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 information

Work, Energy and Power

Work, Energy and Power Work, Energy and Power In this section of the Transport unit, we will look at the energy changes that take place when a force acts upon an object. Energy can t be created or destroyed, it can only be changed

More information

Work, Energy and Power Practice Test 1

Work, Energy and Power Practice Test 1 Name: ate: 1. How much work is required to lift a 2-kilogram mass to a height of 10 meters?. 5 joules. 20 joules. 100 joules. 200 joules 5. ar and car of equal mass travel up a hill. ar moves up the hill

More information

Physical Science Chapter 2. Forces

Physical 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 information

Exam Three Momentum Concept Questions

Exam Three Momentum Concept Questions Exam Three Momentum Concept Questions Isolated Systems 4. A car accelerates from rest. In doing so the absolute value of the car's momentum changes by a certain amount and that of the Earth changes by:

More information

At the skate park on the ramp

At the skate park on the ramp At the skate park on the ramp 1 On the ramp When a cart rolls down a ramp, it begins at rest, but starts moving downward upon release covers more distance each second When a cart rolls up a ramp, it rises

More information

Chapter 6 Work and Energy

Chapter 6 Work and Energy Chapter 6 WORK AND ENERGY PREVIEW Work is the scalar product of the force acting on an object and the displacement through which it acts. When work is done on or by a system, the energy of that system

More information

Forces. When an object is pushed or pulled, we say that a force is exerted on it.

Forces. When an object is pushed or pulled, we say that a force is exerted on it. Forces When an object is pushed or pulled, we say that a force is exerted on it. Forces can Cause an object to start moving Change the speed of a moving object Cause a moving object to stop moving Change

More information

Gravitational Potential Energy

Gravitational Potential Energy Gravitational Potential Energy Consider a ball falling from a height of y 0 =h to the floor at height y=0. A net force of gravity has been acting on the ball as it drops. So the total work done on the

More information

Chapter 3.8 & 6 Solutions

Chapter 3.8 & 6 Solutions Chapter 3.8 & 6 Solutions P3.37. Prepare: We are asked to find period, speed and acceleration. Period and frequency are inverses according to Equation 3.26. To find speed we need to know the distance traveled

More information

Potential / Kinetic Energy Remedial Exercise

Potential / Kinetic Energy Remedial Exercise Potential / Kinetic Energy Remedial Exercise This Conceptual Physics exercise will help you in understanding the Law of Conservation of Energy, and its application to mechanical collisions. Exercise Roles:

More information

Research question: How does the velocity of the balloon depend on how much air is pumped into the balloon?

Research question: How does the velocity of the balloon depend on how much air is pumped into the balloon? Katie Chang 3A For this balloon rocket experiment, we learned how to plan a controlled experiment that also deepened our understanding of the concepts of acceleration and force on an object. My partner

More information

VELOCITY, ACCELERATION, FORCE

VELOCITY, ACCELERATION, FORCE VELOCITY, ACCELERATION, FORCE velocity Velocity v is a vector, with units of meters per second ( m s ). Velocity indicates the rate of change of the object s position ( r ); i.e., velocity tells you how

More information

PS-6.2 Explain the factors that determine potential and kinetic energy and the transformation of one to the other.

PS-6.2 Explain the factors that determine potential and kinetic energy and the transformation of one to the other. PS-6.1 Explain how the law of conservation of energy applies to the transformation of various forms of energy (including mechanical energy, electrical energy, chemical energy, light energy, sound energy,

More information

Work, Power, Energy Multiple Choice. PSI Physics. Multiple Choice Questions

Work, Power, Energy Multiple Choice. PSI Physics. Multiple Choice Questions Work, Power, Energy Multiple Choice PSI Physics Name Multiple Choice Questions 1. A block of mass m is pulled over a distance d by an applied force F which is directed in parallel to the displacement.

More information

force (mass)(acceleration) or F ma The unbalanced force is called the net force, or resultant of all the forces acting on the system.

force (mass)(acceleration) or F ma The unbalanced force is called the net force, or resultant of all the forces acting on the system. 4 Forces 4-1 Forces and Acceleration Vocabulary Force: A push or a pull. When an unbalanced force is exerted on an object, the object accelerates in the direction of the force. The acceleration is proportional

More information

Work and Conservation of Energy

Work and Conservation of Energy Work and Conservation of Energy Topics Covered: 1. The definition of work in physics. 2. The concept of potential energy 3. The concept of kinetic energy 4. Conservation of Energy General Remarks: Two

More information

Friction and Gravity. Friction. Section 2. The Causes of Friction

Friction and Gravity. Friction. Section 2. The Causes of Friction Section 2 Friction and Gravity What happens when you jump on a sled on the side of a snow-covered hill? Without actually doing this, you can predict that the sled will slide down the hill. Now think about

More information

Newton s Laws Quiz Review

Newton s Laws Quiz Review Newton s Laws Quiz Review Name Hour To be properly prepared for this quiz you should be able to do the following: 1) state each of Newton s three laws of motion 2) pick out examples of the three laws from

More information

PHYS 117- Exam I. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

PHYS 117- Exam I. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. PHYS 117- Exam I Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Car A travels from milepost 343 to milepost 349 in 5 minutes. Car B travels

More information

Energy - Key Vocabulary

Energy - Key Vocabulary Energy - Key Vocabulary Term Potential Energy Kinetic Energy Joules Gravity Definition The energy an object possesses due to its position. PE = mgh The energy an object possesses when it is in motion.

More information

WORKSHEET: KINETIC AND POTENTIAL ENERGY PROBLEMS

WORKSHEET: KINETIC AND POTENTIAL ENERGY PROBLEMS WORKSHEET: KINETIC AND POTENTIAL ENERGY PROBLEMS 1. Stored energy or energy due to position is known as Potential energy. 2. The formula for calculating potential energy is mgh. 3. The three factors that

More information

Name Class Date. You do twice as much work. b. You lift two identical books one meter above the ground.

Name Class Date. You do twice as much work. b. You lift two identical books one meter above the ground. Exercises 9.1 Work (pages 145 146) 1. Circle the letter next to the correct mathematical equation for work. work = force distance work = distance force c. work = force distance d. work = force distance

More information

Work Energy & Power. September 2000 Number 05. 1. Work If a force acts on a body and causes it to move, then the force is doing work.

Work Energy & Power. September 2000 Number 05. 1. Work If a force acts on a body and causes it to move, then the force is doing work. PhysicsFactsheet September 2000 Number 05 Work Energy & Power 1. Work If a force acts on a body and causes it to move, then the force is doing work. W = Fs W = work done (J) F = force applied (N) s = distance

More information

physics 111N work & energy

physics 111N work & energy physics 111N work & energy conservation of energy entirely gravitational potential energy kinetic energy turning into gravitational potential energy gravitational potential energy turning into kinetic

More information

Lecture 07: Work and Kinetic Energy. Physics 2210 Fall Semester 2014

Lecture 07: Work and Kinetic Energy. Physics 2210 Fall Semester 2014 Lecture 07: Work and Kinetic Energy Physics 2210 Fall Semester 2014 Announcements Schedule next few weeks: 9/08 Unit 3 9/10 Unit 4 9/15 Unit 5 (guest lecturer) 9/17 Unit 6 (guest lecturer) 9/22 Unit 7,

More information

Name: Partners: Period: Coaster Option: 1. In the space below, make a sketch of your roller coaster.

Name: Partners: Period: Coaster Option: 1. In the space below, make a sketch of your roller coaster. 1. In the space below, make a sketch of your roller coaster. 2. On your sketch, label different areas of acceleration. Put a next to an area of negative acceleration, a + next to an area of positive acceleration,

More information

1. Mass, Force and Gravity

1. Mass, Force and Gravity STE Physics Intro Name 1. Mass, Force and Gravity Before attempting to understand force, we need to look at mass and acceleration. a) What does mass measure? The quantity of matter(atoms) b) What is the

More information

Lecture 6. Weight. Tension. Normal Force. Static Friction. Cutnell+Johnson: 4.8-4.12, second half of section 4.7

Lecture 6. Weight. Tension. Normal Force. Static Friction. Cutnell+Johnson: 4.8-4.12, second half of section 4.7 Lecture 6 Weight Tension Normal Force Static Friction Cutnell+Johnson: 4.8-4.12, second half of section 4.7 In this lecture, I m going to discuss four different kinds of forces: weight, tension, the normal

More information

Unit 2 Force and Motion

Unit 2 Force and Motion Force and Motion Unit 2 Force and Motion Learning Goal (TEKS): Identify and describe the changes in position, direction, and speed of an object when acted upon by unbalanced forces. This means: We are

More information

Laboratory Report Scoring and Cover Sheet

Laboratory Report Scoring and Cover Sheet Laboratory Report Scoring and Cover Sheet Title of Lab _Newton s Laws Course and Lab Section Number: PHY 1103-100 Date _23 Sept 2014 Principle Investigator _Thomas Edison Co-Investigator _Nikola Tesla

More information

BHS Freshman Physics Review. Chapter 2 Linear Motion Physics is the oldest science (astronomy) and the foundation for every other science.

BHS Freshman Physics Review. Chapter 2 Linear Motion Physics is the oldest science (astronomy) and the foundation for every other science. BHS Freshman Physics Review Chapter 2 Linear Motion Physics is the oldest science (astronomy) and the foundation for every other science. Galileo (1564-1642): 1 st true scientist and 1 st person to use

More information

circular motion & gravitation physics 111N

circular 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 information

Free Fall: Observing and Analyzing the Free Fall Motion of a Bouncing Ping-Pong Ball and Calculating the Free Fall Acceleration (Teacher s Guide)

Free Fall: Observing and Analyzing the Free Fall Motion of a Bouncing Ping-Pong Ball and Calculating the Free Fall Acceleration (Teacher s Guide) Free Fall: Observing and Analyzing the Free Fall Motion of a Bouncing Ping-Pong Ball and Calculating the Free Fall Acceleration (Teacher s Guide) 2012 WARD S Science v.11/12 OVERVIEW Students will measure

More information

Kinetic Energy (A) stays the same stays the same (B) increases increases (C) stays the same increases (D) increases stays the same.

Kinetic Energy (A) stays the same stays the same (B) increases increases (C) stays the same increases (D) increases stays the same. 1. A cart full of water travels horizontally on a frictionless track with initial velocity v. As shown in the diagram, in the back wall of the cart there is a small opening near the bottom of the wall

More information

The Physics of Kicking a Soccer Ball

The Physics of Kicking a Soccer Ball The Physics of Kicking a Soccer Ball Shael Brown Grade 8 Table of Contents Introduction...1 What actually happens when you kick a soccer ball?...2 Who kicks harder shorter or taller people?...4 How much

More information

Forces. Definition Friction Falling Objects Projectiles Newton s Laws of Motion Momentum Universal Forces Fluid Pressure Hydraulics Buoyancy

Forces. Definition Friction Falling Objects Projectiles Newton s Laws of Motion Momentum Universal Forces Fluid Pressure Hydraulics Buoyancy Forces Definition Friction Falling Objects Projectiles Newton s Laws of Motion Momentum Universal Forces Fluid Pressure Hydraulics Buoyancy Definition of Force Force = a push or pull that causes a change

More information

UNIT 2 GCSE PHYSICS 2.2.1 Forces and Energy 2011 FXA WORK DONE (J) = ENERGY TRANSFERRED (J) WORK

UNIT 2 GCSE PHYSICS 2.2.1 Forces and Energy 2011 FXA WORK DONE (J) = ENERGY TRANSFERRED (J) WORK 29 When a force causes an object to move through a distance, work is done. Work done, force and distance are related by the equation : W = F x d WORK When a force is applied to an object and cause it to

More information

How Rockets Work Newton s Laws of Motion

How Rockets Work Newton s Laws of Motion How Rockets Work Whether flying a small model rocket or launching a giant cargo rocket to Mars, the principles of how rockets work are exactly the same. Understanding and applying these principles means

More information

CHAPTER 6 WORK AND ENERGY

CHAPTER 6 WORK AND ENERGY CHAPTER 6 WORK AND ENERGY CONCEPTUAL QUESTIONS. REASONING AND SOLUTION The work done by F in moving the box through a displacement s is W = ( F cos 0 ) s= Fs. The work done by F is W = ( F cos θ). s From

More information

Educational Innovations

Educational Innovations Educational Innovations Background Forces and Motion MAR-600 Wall Coaster Motion is caused by forces. Motion can be described. Motion follows rules. There are many forces and principles involved with motion.

More information

Lesson 39: Kinetic Energy & Potential Energy

Lesson 39: Kinetic Energy & Potential Energy Lesson 39: Kinetic Energy & Potential Energy Total Mechanical Energy We sometimes call the total energy of an object (potential and kinetic) the total mechanical energy of an object. Mechanical energy

More information

Worksheet #1 Free Body or Force diagrams

Worksheet #1 Free Body or Force diagrams Worksheet #1 Free Body or Force diagrams Drawing Free-Body Diagrams Free-body diagrams are diagrams used to show the relative magnitude and direction of all forces acting upon an object in a given situation.

More information

Newton s Laws Force and Motion

Newton s Laws Force and Motion CLIL Project Physics in English Anno scolastico 2013-2014 Newton s Laws Force and Motion Lecture 2 Classe 3 a A Linguistico Istituto Superiore Marini-Gioia - AMALFI Content of the unit: Newton s Laws DYNAMIC

More information

Review Chapters 2, 3, 4, 5

Review Chapters 2, 3, 4, 5 Review Chapters 2, 3, 4, 5 4) The gain in speed each second for a freely-falling object is about A) 0. B) 5 m/s. C) 10 m/s. D) 20 m/s. E) depends on the initial speed 9) Whirl a rock at the end of a string

More information

Practice 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: 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 information

Conceptual Questions: Forces and Newton s Laws

Conceptual Questions: Forces and Newton s Laws Conceptual Questions: Forces and Newton s Laws 1. An object can have motion only if a net force acts on it. his statement is a. true b. false 2. And the reason for this (refer to previous question) is

More information

Name Period WORKSHEET: KINETIC AND POTENTIAL ENERGY PROBLEMS. 1. Stored energy or energy due to position is known as energy.

Name Period WORKSHEET: KINETIC AND POTENTIAL ENERGY PROBLEMS. 1. Stored energy or energy due to position is known as energy. Name Period Date WORKSHEET: KINETIC AND POTENTIAL ENERGY PROBLEMS 1. Stored energy or energy due to position is known as energy. 2. The formula for calculating potential energy is. 3. The three factors

More information

Chapter 6. Work and Energy

Chapter 6. Work and Energy Chapter 6 Work and Energy The concept of forces acting on a mass (one object) is intimately related to the concept of ENERGY production or storage. A mass accelerated to a non-zero speed carries energy

More information

Name per due date mail box

Name per due date mail box Name per due date mail box Rolling Momentum Lab (1 pt for complete header) Today in lab, we will be experimenting with momentum and measuring the actual force of impact due to momentum of several rolling

More information

1. The Kinetic Theory of Matter states that all matter is composed of atoms and molecules that are in a constant state of constant random motion

1. The Kinetic Theory of Matter states that all matter is composed of atoms and molecules that are in a constant state of constant random motion Physical Science Period: Name: ANSWER KEY Date: Practice Test for Unit 3: Ch. 3, and some of 15 and 16: Kinetic Theory of Matter, States of matter, and and thermodynamics, and gas laws. 1. The Kinetic

More information

GRAVITATIONAL FIELDS PHYSICS 20 GRAVITATIONAL FORCES. Gravitational Fields (or Acceleration Due to Gravity) Symbol: Definition: Units:

GRAVITATIONAL FIELDS PHYSICS 20 GRAVITATIONAL FORCES. Gravitational Fields (or Acceleration Due to Gravity) Symbol: Definition: Units: GRAVITATIONAL FIELDS Gravitational Fields (or Acceleration Due to Gravity) Symbol: Definition: Units: Formula Description This is the formula for force due to gravity or as we call it, weight. Relevant

More information

Proof of the conservation of momentum and kinetic energy

Proof of the conservation of momentum and kinetic energy Experiment 04 Proof of the conservation of momentum and kinetic energy By Christian Redeker 27.10.2007 Contents 1.) Hypothesis...3 2.) Diagram...7 3.) Method...7 3.1) Apparatus...7 3.2) Procedure...7 4.)

More information

A Determination of g, the Acceleration Due to Gravity, from Newton's Laws of Motion

A Determination of g, the Acceleration Due to Gravity, from Newton's Laws of Motion A Determination of g, the Acceleration Due to Gravity, from Newton's Laws of Motion Objective In the experiment you will determine the cart acceleration, a, and the friction force, f, experimentally for

More information

Work, Energy and Power

Work, Energy and Power Name: KEY Work, Energy and Power Objectives: 1. To understand work and its relation to energy. 2. To understand how energy can be transformed from one form into another. 3. To compute the power from the

More information

Proving the Law of Conservation of Energy

Proving the Law of Conservation of Energy Table of Contents List of Tables & Figures: Table 1: Data/6 Figure 1: Example Diagram/4 Figure 2: Setup Diagram/8 1. Abstract/2 2. Introduction & Discussion/3 3. Procedure/5 4. Results/6 5. Summary/6 Proving

More information

Ch 7 Kinetic Energy and Work. Question: 7 Problems: 3, 7, 11, 17, 23, 27, 35, 37, 41, 43

Ch 7 Kinetic Energy and Work. Question: 7 Problems: 3, 7, 11, 17, 23, 27, 35, 37, 41, 43 Ch 7 Kinetic Energy and Work Question: 7 Problems: 3, 7, 11, 17, 23, 27, 35, 37, 41, 43 Technical definition of energy a scalar quantity that is associated with that state of one or more objects The state

More information

Physics 125 Practice Exam #3 Chapters 6-7 Professor Siegel

Physics 125 Practice Exam #3 Chapters 6-7 Professor Siegel Physics 125 Practice Exam #3 Chapters 6-7 Professor Siegel Name: Lab Day: 1. A concrete block is pulled 7.0 m across a frictionless surface by means of a rope. The tension in the rope is 40 N; and the

More information

Newton s Law of Universal Gravitation

Newton 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 information

Lesson 3 - Understanding Energy (with a Pendulum)

Lesson 3 - Understanding Energy (with a Pendulum) Lesson 3 - Understanding Energy (with a Pendulum) Introduction This lesson is meant to introduce energy and conservation of energy and is a continuation of the fundamentals of roller coaster engineering.

More information

Name: Date: Period: Gravity Study Guide

Name: 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 information

Force. Force as a Vector Real Forces versus Convenience The System Mass Newton s Second Law. Outline

Force. Force as a Vector Real Forces versus Convenience The System Mass Newton s Second Law. Outline Force Force as a Vector Real Forces versus Convenience The System Mass Newton s Second Law Outline Force as a Vector Forces are vectors (magnitude and direction) Drawn so the vector s tail originates at

More information

Balanced and Unbalanced Forces

Balanced and Unbalanced Forces 1 Balanced and Unbalanced Forces Lesson Created by Carlos Irizarry, George B. Swift Specialty School, Chicago, Illinois Purpose To fully appreciate and make a connection to Newton s Laws, students must

More information

Name Class Period. F = G m 1 m 2 d 2. G =6.67 x 10-11 Nm 2 /kg 2

Name Class Period. F = G m 1 m 2 d 2. G =6.67 x 10-11 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 information

Work, Energy & Momentum Homework Packet Worksheet 1: This is a lot of work!

Work, Energy & Momentum Homework Packet Worksheet 1: This is a lot of work! Work, Energy & Momentum Homework Packet Worksheet 1: This is a lot of work! 1. A student holds her 1.5-kg psychology textbook out of a second floor classroom window until her arm is tired; then she releases

More information

III. Applications of Force and Motion Concepts. Concept Review. Conflicting Contentions. 1. Airplane Drop 2. Moving Ball Toss 3. Galileo s Argument

III. Applications of Force and Motion Concepts. Concept Review. Conflicting Contentions. 1. Airplane Drop 2. Moving Ball Toss 3. Galileo s Argument III. Applications of Force and Motion Concepts Concept Review Conflicting Contentions 1. Airplane Drop 2. Moving Ball Toss 3. Galileo s Argument Qualitative Reasoning 1. Dropping Balls 2. Spinning Bug

More information

ENERGYand WORK (PART I and II) 9-MAC

ENERGYand WORK (PART I and II) 9-MAC ENERGYand WORK (PART I and II) 9-MAC Purpose: To understand work, potential energy, & kinetic energy. To understand conservation of energy and how energy is converted from one form to the other. Apparatus:

More information

What Is Energy? Energy and Work: Working Together. 124 Chapter 5 Energy and Energy Resources

What Is Energy? Energy and Work: Working Together. 124 Chapter 5 Energy and Energy Resources 1 What You Will Learn Explain the relationship between energy and work. Compare kinetic and potential energy. Describe the different forms of energy. Vocabulary energy kinetic energy potential energy mechanical

More information

TEACHER ANSWER KEY November 12, 2003. Phys - Vectors 11-13-2003

TEACHER ANSWER KEY November 12, 2003. Phys - Vectors 11-13-2003 Phys - Vectors 11-13-2003 TEACHER ANSWER KEY November 12, 2003 5 1. A 1.5-kilogram lab cart is accelerated uniformly from rest to a speed of 2.0 meters per second in 0.50 second. What is the magnitude

More information

Forces between charges

Forces between charges Forces between charges Two small objects each with a net charge of Q (where Q is a positive number) exert a force of magnitude F on each other. We replace one of the objects with another whose net charge

More information

WORK DONE BY A CONSTANT FORCE

WORK DONE BY A CONSTANT FORCE WORK DONE BY A CONSTANT FORCE The definition of work, W, when a constant force (F) is in the direction of displacement (d) is W = Fd SI unit is the Newton-meter (Nm) = Joule, J If you exert a force of

More information

Momentum Crash Course

Momentum Crash Course Objective: To study momentum and its role in car crashes. Grade Level: 5-8 Subject(s): Science, Mathematics Prep Time: < 10 minutes Duration: One class period Materials Category: Household National Education

More information

What Do You Think? For You To Do GOALS

What Do You Think? For You To Do GOALS Activity 2 Newton s Law of Universal Gravitation GOALS In this activity you will: Explore the relationship between distance of a light source and intensity of light. Graph and analyze the relationship

More information

7 TH GRADE SCIENCE REVIEW

7 TH GRADE SCIENCE REVIEW 7 TH GRADE SCIENCE REVIEW The motion of an object is always judged with respect to some other object or point. When an object changes position over time relative to a reference point, the object is in

More information

Ideal Cable. Linear Spring - 1. Cables, Springs and Pulleys

Ideal Cable. Linear Spring - 1. Cables, Springs and Pulleys Cables, Springs and Pulleys ME 202 Ideal Cable Neglect weight (massless) Neglect bending stiffness Force parallel to cable Force only tensile (cable taut) Neglect stretching (inextensible) 1 2 Sketch a

More information

Chapter 5 Using Newton s Laws: Friction, Circular Motion, Drag Forces. Copyright 2009 Pearson Education, Inc.

Chapter 5 Using Newton s Laws: Friction, Circular Motion, Drag Forces. Copyright 2009 Pearson Education, Inc. Chapter 5 Using Newton s Laws: Friction, Circular Motion, Drag Forces Units of Chapter 5 Applications of Newton s Laws Involving Friction Uniform Circular Motion Kinematics Dynamics of Uniform Circular

More information

Roanoke Pinball Museum Key Concepts

Roanoke Pinball Museum Key Concepts Roanoke Pinball Museum Key Concepts What are Pinball Machines Made of? SOL 3.3 Many different materials are used to make a pinball machine: 1. Steel: The pinball is made of steel, so it has a lot of mass.

More information

KE =? v o. Page 1 of 12

KE =? v o. Page 1 of 12 Page 1 of 12 CTEnergy-1. A mass m is at the end of light (massless) rod of length R, the other end of which has a frictionless pivot so the rod can swing in a vertical plane. The rod is initially horizontal

More information

Explore 3: Crash Test Dummies

Explore 3: Crash Test Dummies Explore : Crash Test Dummies Type of Lesson: Learning Goal & Instructiona l Objectives Content with Process: Focus on constructing knowledge through active learning. Students investigate Newton s first

More information

Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion. Physics is about forces and how the world around us reacts to these forces.

Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion. Physics is about forces and how the world around us reacts to these forces. Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion Physics is about forces and how the world around us reacts to these forces. Whats a force? Contact and non-contact forces. Whats a

More information

Sample Questions for the AP Physics 1 Exam

Sample 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 information