Problem 1RCQ: Which has a greater momentum-a heavy truck at rest or a moving skateboard? Problem 2RCQ: How can a huge ship have an enormous momentum when it moves relatively slowly? Problem 3RCQ: How does impulse differ from force? Problem 4RCQ: What are the two ways in which the impulse exerted on something can be increased? Problem 5RCQ: For the same force, which cannon imparts the greater speed to a cannonball-a long cannon or a short... Problem 6RCQ: Consider a baseball that is caught and thrown at the same speed. Which case illustrates the greatest... Problem 7RCQ: In the preceding question, which case requires the greatest impulse? Problem 8RCQ: Can you produce a net impulse on an automobile by sitting inside and pushing on the dashboard?... Problem 9RCQ: What does it mean to say that a quantity is conserved? Problem 10RCQ: Distinguish between an elastic collision and an inelastic collision. For which type of collision is... Problem 11RCQ: Railroad car A rolls at a certain speed and collides elastically with car B of the same mass. After... Problem 12RCQ: If the equally massive cars of the preceding question stick together after colliding inelastically,... Problem 13RCQ: When is energy most evident? Problem 14RCQ: What do we call the quantity force distance, and what quantity does it change? Problem 15RCQ: In what units are work and energy measured? Problem 16RCQ: True or false: One watt is the unit of power equivalent to 1 joule per second. Problem 17RCQ: How many watts of power are expended when a force of 6 N moves a book 2 m in a time interval of 3 s... Problem 18RCQ: A car is lifted a certain distance in a service station and therefore has potential energy with... Problem 19RCQ: Two cars, one twice as heavy as the other, are lifted to the same height in a service station. How... Problem 20RCQ: When a car travels at 50 km/h, it has kinetic energy. How much more kinetic energy does it have at... Problem 21RCQ: What is the evidence for saying whether or not work is done on an object? Problem 22RCQ: The brakes do a certain amount of work to stop a car that is moving at a particular speed. How much... Problem 23RCQ: Cite the law of energy conservation. Problem 24RCQ: What is the source of energy that powers a hydroelectric power plant? Problem 25RCQ: Can a machine multiply input force? Input distance? Input energy? If your three answers are the... Problem 26RCQ: A force of 50 N applied to the end of a lever moves that end a certain distance. If the other end of... Problem 27RCQ: Is it possible to design a machine that has an efficiency greater than 100 ? Discuss. Problem 28TIS: a Why is it a good idea to have your hand extended forward when you are getting ready to catch a... Problem 29TIS: In Figure 4.8, how does the force that Cassy exerts on the bricks compare with the force exerted on... Problem 30TIS: How will the impulse differ if Cassys hand bounces back when striking the bricks? Problem 31TIS: We know that falling on a mat is preferable to falling on a concrete floor. Explain why in terms of... Problem 32TIS: In terms of the impulse-momentum relationship, explain why falling and bouncing from a solid... Problem 33TIS: The word burn is often used to describe the process of cellular respiration, in which cells release... Problem 34TIS: In what sense are you powered by solar energy? Problem 39PC: Calculate the momentum of a 10-kg bowling ball rolling at 3 m/s. Problem 40PC: Show that the momentum of a 50-kg carton that slides at 3 m/s across an icy surface is 150 kgm/s Problem 41PC: Calculate the impulse that occurs when an average force of 10 N is exerted on a cart for 5 s. Problem 42PC: Show that an impulse of 100 Ns occurs when the same 10-N force acts on the cart for twice the time. Problem 43PC: Calculate the work done when a force of 2 N moves a book 3 m. Problem 44PC: Show that 45 J of work is done when a 15-N force pushes a cart 3 m. Problem 45PC: Calculate the watts of power expended when a force of 1 N moves a book 2 m in a time interval of 1... Problem 46PC: Show that 140 W of power is expended when a 20-N force pushes a cart 3.5 m in a time of 0.5 s. Problem 47PC: How much PE does a 1.5 kg book gain when lifted 2 m ? 4 m ? (Letg=10N/kg.) Problem 48PC: Show that there is a 600-J increase in potential energy when a 20-kg block of ice is lifted a... Problem 49PC: Calculate the KE of a 1-kg parrot flying at 6 m/s. Problem 50PC: Show that the KE of a 3-kg dog running at 4 m/s is 24 J. Problem 51PC: How much work is required to increase the kinetic energy of a motor scooter by 4000 J. Problem 52PC: Show that a 50-J change in kinetic energy occurs when a model airplane on takeoff is moved a... Problem 53TC: The mass and speed of three vehicles, A, B and C, are shown. Rank them from greatest to least for a... Problem 54TC Problem 55TC: The roller coaster stats from rest at point A. Rank these quantities from greatest to least at each... Problem 56TC: Rank the scale readings from greatest to least ignoring friction. . Problem 57TS: A car with a mass of 1000kgmoves at 20m/s. Show that the braking force needed to bring the car to a... Problem 58TS: A railroad diesel engine weighs four times as much as a freight car. If the diesel engine coasts at... Problem 59TS: A 5kg fish swimming at 1m/s swallows an absent minded 1kg fish at rest. Show that the speed of the... Problem 60TS: What would be the speed of the larger fish if the smaller fish were swimming towards it at 4m/s. Problem 61TS: Jeannie Beanie mass 40kg, standing on a slippery ice, catches her dog Daisy mass 20kg, who leaps... Problem 62TS: Consider the inelastic collision between the two freight cars in Figure 4.12. The momentum before... Problem 63TS: This question is typical on some drivers licence exams: A car moving at 50km/hskids 15mwith locked... Problem 64TS: In the hydraulic machine shown, it is observed that when the small piston is pushed down 10cm, the... Problem 65TS: Consider a car with 25% efficient engine that and encounters an average retarding force of 500N.... Problem 66TS: When a cyclist expends 1000W of power to deliver mechanical energy to her bicycle at a rate of 100W,... Problem 67TS: The decrease in PE of a freely falling object equals its gain in KE, in accord with the conservation... Problem 68TE: A Mars vehicle is tested on Earth at a speed of 12km/h. When it travels at the same speed on the... Problem 69TE: How can the momentum of a speeding bullet be the same as the momentum of a ship moving towards a... Problem 70TE: Distinguish between force and impulse. . Problem 71TE: What are the two ways to increase or decrease impulse? Problem 72TE: Why are automobiles designed to crumple upon impact? Problem 73TE: Why might a glass wine survive a fall onto a carpeted floor but not onto a concrete floor? Problem 74TE: If you throw an egg against a wall, the egg will break. If you throw an egg at the same speed into a... Problem 75TE: Railroad cars are loosely coupled so that there is a noticeable delay from the time the first car is... Problem 76TE: When a cannon with a long barrel is fired, the force of the expanding gases acts on the cannonball... Problem 77TE: Why does Howies block Figure 4.3 topple when the swinging dart bounces from it, but not when the... Problem 78TE: You are on small raft next to a dock, and you jump from the raft only to fall in water. What physics... Problem 79TE: When travelling in your car at highway speed, the momentum of a bug is suddenly changed as it... Problem 80TE: Freddy Frog drops vertically from a tree onto a horizontally moving skateboard. The skateboard... Problem 81TE Problem 82TE: Can something have energy without having momentum? Explain. Can something have momentum without... Problem 83TE: Which requires more work: stretching a strong spring a certain distance or stretching a weak spring... Problem 84TE: Why do you run out of breath when running up the stairs but not when walking up the stairs? Problem 85TE: Distinguish between work and power. Problem 86TE: Relative to the floor in a library, books on the top shelf have potential energy. Can a book on a... Problem 87TE: If 300 joules is required to lift an object to a given height, how much potential energy does it... Problem 88TE: When the velocity of an object is doubled, by what factor is its momentum changed? By what factor is... Problem 89TE: You and a flight attended tosses a ball back and forth in an airplane in a flight. Does the KE of... Problem 90TE: A child can throw a baseball at 20 mph. Some professional ball players can throw a baseball at 100... Problem 91TE Problem 92TE: When a cannon with a long barrel is fired, the force of expanding gases act on the cannonball for a... Problem 93TE: Consider a pendulum swinging to and fro. At what point in its motion is the KE of the pendulum bob... Problem 94TE: A physics instructor demonstrates energy conservation by releasing a heavy pendulum bob, as shown in... Problem 95TE: An apple hanging from a limb has potential energy due to its height. If it falls, what becomes of... Problem 96TE: In an effort to combat wasteful habits, we often urge others to conserve energy by turning off... Problem 97TE: Why bother using a machine if it cannot multiply work input to achieve greater work input? Problem 98TE: In the ideal pulley system shown, Block A has mass 10kg. Explain why Block B must have 20kg. Problem 99TDI: Why is a punch more powerful with a bare fist than with a boxing glove? Problem 100TDI: A boxer can punch a heavy bag for more than an hour without tiring but will tire more quickly when... Problem 101TDI: A fully dressed person is at rest in the middle of a pond on perfectly frictionless ice and must... Problem 102TDI: Why is it difficult for a firefighter to hold a hose that ejects large quantities of water at high... Problem 103TDI: If a Mack truck and Honda Civic have a head-on collision, which vehicle will experience the greater... Problem 104TDI: If an automobile has an engine that was 100% efficient, would it be warm to your touch? Would its... Problem 105TDI: Discuss the design of the roller coaster shown in the sketch in terms of conservation of energy. Problem 106TDI: Consider the identical balls released from rest on the tracks A and B as shown. When each ball has... Problem 107TDI: Consider the swinging balls apparatus shown. If two balls ae lifted and released, momentum is... Problem 1RAT: A freight train rolls along a track with considerable momentum. If it rolls at the same speed but... Problem 2RAT: If Fast Freda doubles her running speed, she also doubles her a momentum. b kinetic energy. c both... Problem 3RAT: A big fish swims upon and swallows a small fish at rest. Immediately after lunch, the fattened big... Problem 4RAT: Which of these equations best illustrates the usefulness of automobile air bags? a F=ma b Ft=mv c... Problem 5RAT: Which of these equations is best for calculating the distance a fast-moving bike will skid when its... Problem 6RAT: The power required to raise a 100-kg crate a vertical distance of 2 m in 4 s is a 200 W b 500 W c... Problem 7RAT: A model car with three times as much speed as another has kinetic energy that is a the same. b... Problem 8RAT: Nellie lifts a 100-N crate with an ideal pulley system by pulling a rope downward with 25 N of... Problem 9RAT: When 100 J are put into a device that puts out 40 J of useful work, the efficiency of the device is... Problem 10RAT: A simple machine CANNOT multiply a force. b distance. c energy. d but in certain cases it can... format_list_bulleted