Scctipn4-JQiij, 1hat IS the mass of an object that ran be aoeierated lioritontalk at 4 4 ui/sr by a force of )7() N. Date. Period.

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1 Date Period Name CHAPTER 4 Scctipn4-JQiij, 1. \\ hat are the two omponents that make up a force? 2. low can the forces acting Ofl an object be combined to show the net force acting on an object? 3. \\!l1 it is equilibritin in terms of for(es? 4. What is the acceleration of a 3 kg mass that has a force of 270 N applied to ii horitontal iv? 5. :\ crate is pushed ast across a fri tioiiiess surface with a force of 2-TO N and pulled to the last by a lope with a force of 120 N. \\ hat is the net torce on the crate 6. 1hat S the mass of an object that ran be aoeierated lioritontalk at 4 4 ui/sr by a force of )7() N \\ iiir ijies ala]! roh!crii ( iapieis?esoiiiies 123

2 Period Date - Name CHAPTER 4r ScstiOw4ZQw, 1. Upon what two factors does the weight of an objet depend? 2. Define terminal velocity. & Name one situation in which an object is weightless. 4. During a tug-of-war. one side pulls with a force of 2,000.0 N toward the north, and the other side pulls with a force of 12,0100 toward the south, What is the net force on the mass of all the pullers You may want to draw a free-body diagram to help you answer the question 5. While stauonar on ah you have a vughr of E 0 N Whcn in an elevator that accelerates upward your weigl temporanly bee mes )9) N W r dcs ending your weight temporarily becomes 510 N. You may want to dra v frc c-hod diagran to help you inswer thsc questions a. What is the acelerarion you expene we as the elevator moves up? b. What is the acceleration you experience as the elevator moves down? 124 C1zapree 7 5 Resources Plnvic: Principles and Problems

3 Date Period Name CHAPTER 1. What are all forces the result of? 2. Define tension. 3. Define normal force. 4. A large safe being lifted into a building with a pulley snaps the chain that supports it and falls toward Earth. f the safe has a mass of 15,000 kg, what is the acceleration of Earth toward the safe? 2? 5. What is the tension in a rope that is being used to accelerate a kg crate upward at 1.2 m/s Physics: Principles and Problems Chapters 1 5 Resources 125

4 ( opynfl cinin on \kc w d vinon i h \ ba V liii (. on panws h Motion and Newton s Second Law 6O E 4O 0 > 2O ZO 25 Time (h)

5 time = 0.75 h in m/s 2? 1. What is the acceleration of the object whose motion is recorded in this graph from time = 0.0 to Motion and Newton s Second Law 4 Transnarencv 4-2 Worksheet 134 Chapters 15 Resources Physics: Principles and Problems 8. What constant aceleration would have achieved the same velocity over the same period of time? Give your answer in m/s 2. were 120,000 kg? 7. What force would be needed to accelerate the object in the interval from 1.75 h to 2.5 h if its mass mass were 120,000 kg? 6 What force would be needed to accelerate the object in the interval from 0.75 h to 1.75 h if its 0.75 h if its mass were 120,000 kg? 5. What force would he needed to accelerate the object in the interval from time = 0.0 h to time = 4. What is the final velocity of this object in m/s? 3, What is the acceleration from 1.75 h to 2.5 h in rn/s 2? 2 What is the acceleration from 0.75 h to 1.75 h in m/s 2? Period Name

6 4 on bowling bafl Direction of motion L Newton s Third law: nteraction Pairs nteraction pair Forces acting on bowling ball on bow ball F ball on Earth on bowling ball

7 1. What three agents are exerting forces in this diagram? Newton s Third Law: nteraction Pairs Trja!cncQkshec 136 Chapters 1-5 Resources Physics: Principles and Problems 5. f all the forces in the diagram are balanced, why does the bowling ball not remain stationary? 4. What forces act only on the hand? Only on Earth? Only on the bowling ball? 3. List the interaction pairs of forces. How do you know that these are interaction pairs? 2. Describe each force acting in this diagram and provide its symbol. Name_ t

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9 Date Period Name 4r Transoarencv 4-4 Worksheet Weight and Normal Force L Define weight. 2. Define normal force. 3. n which figure is the box s weight equal to the normal force in magnitude? 4. n which figure is the magnitude of the normal force greater than the weight of the box? 5. Are mass and gravity the only factors that contribute to the normal force of an object? 6 n which figure (or figures) does the box have an apparent weight different from that caused by its mass and the effect of gravity alone? Physics: Principles and Problems

10 Date Period Name CHAPTER r44!!t: Forces Understanding Physics Concepts Circle the letter of the choice that best completes the statement. 1. Moving faster as you pedal your bicycle harder on a level road demonstrates Newton s law. 2. a. first c. third b. second a. no a. the force of gravity b. newtons 6. The gravitational force exerted by a large body, such as Earth, is a. weight b. mass 7. The force exerted by any segment of a string or rope on an adjoining segment is a. the drag force b. tension 8. The normal force is the a. perpendicular field b. parallel contact 9. The force exerted by a fluid on an object moving through the fluid is a. tension b. thrust d. gravity According to Newton s law, an object with no net force acting on it remains at rest or in motion with a constant velocity. a. first b. second c third d. apple 3. f you push against a wall, the wall pushes back against you with b. less 4. An object is in equilibrium if a. it has no weight b. the net force on it is zero 5. Mass and weight are related by C. equal d. more C. it is accelerating d. only one force is acting on it c. friction d. inertia c. acceleration d. apparent weight C. friction d. the force of gravity force, force exerted by a surface on another object C. perpendicular contact d. parallel field c. the drag force d. the force of gravity Ph ics: Princip]e.. and Pmblcrns C/iapteis 1-3 Resotiues 139

11 Complete the statement by writing the correct term in the space provided. b. apparent weight a. acceleration C. terminal velocity force of gravity, the object attains d. maximum mass 10. When the drag force on an object equals the w# aw p 140 ( iapreu 1 5 Resources J hvsicc: Principles and Robeim. two objects. 22. The force is a support force resulting from the contact of According to Newton s third law, the two forces that make up an Tension is the specific name for the force exerted by a(n) interaction pair are equal in but in direction. 9. All forces result from between objects. object s and its 18. The effect of drag on an object s motion is determined by the 17.. An object with no apparent weight experiences and the mass of the object. 16. he weight of an object depends upon the aceleration due to 15 An object with no net force auing on it is in addition to find the net force 14.. You can add the forces acting upon an object by using the object, 13.. n a freebody diagram, you draw the force vectors leading Forces have both direction and on it. An object that experiences a push or a pull has a exerted 4, Chanter Assessment continued Name

12 Name continued tersess!!!e - Thinking Critically Answer the follou ing questions. Use complete sentences. 1. Explain the relationship between mass and weight on Earth. Would this relationship change on the planet Mars? Give a reason for your answer. 2. You are in an elevator traveling from the lobby to the top of a building. As it slows to a stop on the top floor, what happens to your apparent weight? 3. n the drawing below, use arrows to show the two horizontal and two vertical forces acting on the boat as it is pulled to the shore at a constant speed. s there a net force on the boat? Explain. Physics: Principles dnd Problems Chapters 1 5 Resources 141

13 Name 4 Chanter Assessment continued 4. Explain what is meant by an interaction pair. Use the boat in the drawing for question 3 to give an example. 5. Suppose you pull on a rope tied to a large carton, hut you cannot move the carton. What forces are acting on your hand? Draw a freehody diagram. 6. You are skydiving. The plane takes you to a typical jump altitude of 3000 m. When you step out of the plane, you accelerate downward at 190 kph for about 10 S. Then you enter 45 s of free fall this is when you fall at terminal velocity. At 760 m your parachute deploys. f you want to experi ence more time in free fall! what should you do? a. Draw a free-body diagram of your body when you first step out of the plane. b. Draw a frec-body diagram of your body when you are in a free fall. c. Draw a free-body diagram of your body immediately after your parachute has deployed. 142 tjzamers 1 5 Resources Physics: Principles and Problems

14 1 Name continued Chapter Assessment 4 Applying Physics Knowledge Answer the jollowing questions. Show your calculations. 2? 1. What force is required to accelerate a 6.0-kg bowling ball at +2.0 m/s 2. What is the mass of a cat that weighs 30.0 N? 3. What is the tension in a rope that is supporting a 4.2-kg bucket? 4. A net force of 25 N acts on an object. 1-ind the single force that vill produce equilibrium. Answer the ftllowing questions. Show your calculations. Draw a free-body diagram to help you ansu er the questions. 5. An elevator with a mass of 1.1OX l& kg accelerates upward at 0.45 m/s. \\hat is the force acting on the elevator s support cable? 6. A rocket weighs 2,0X 10 N. ts engines exert a force of -r25x io N at liftoff. a. What is the mass of the rocket at liftoff? b What is the rocket s acceleration when it lifts off? Plwsics: Prim iples and Jmb1iiis (hiaptei 1 1? tine 143

15 Name &r hptcrassessmcjit_ 7. A 47-N box is pulled along a frictionless horizontal surface by a 25-N weight hanging from a cord on a frictionless pulley a What is the acceleration of the box and the weight? b What force is exerted on the cord? 8. A stepping stool is constructed so that it collapses when the normal force exceeds 1100 N. You are assisting a welder who weighs 102 kg and is on the top step of the stepping stool. You pass the welder a torch and a fuel tank that weigh a combined 14 kg. The welder refuses to take both items from you. Explain why. Show your calculations. r j 144 (h q ter S Resoures Physics: Principles and Problems