3) Which of the following quantities has units of a displacement? (There could be more than one correct choice.)

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1 FLEX Physical Sciences AP Physics 1 (Honors Physics) Final Homework Exam 1) A toy rocket is launched vertically from ground level at time t = 0 s. The rocket engine provides constant upward acceleration during the burn phase. At the instant of engine burnout, the rocket has risen to 49.0 m and acquired an upward velocity of 60.0 m/s. The rocket continues to rise with insignificant air resistance in unpowered flight, reaches maximum height, and falls back to the ground. The maximum height reached by the rocket is closest to E) 2) A ball is thrown straight up, reaches a maximum height, then falls to its initial height. Which of the following statements about the direction of the velocity and acceleration of the ball as it is going up is correct? 3) Which of the following quantities has units of a displacement? (There could be more than one correct choice.) 9.8 m/s2 E) 32 ft/s2 vertically downward 4) Abby throws a ball straight up and times it. She sees that the ball goes by the top of a flagpole after 0.50 s and reaches the level of the top of the pole after a total elapsed time of 4.1 s. What was the speed of the ball at as it passed the top of the flagpole? Neglect air resistance. E) 5) A certain test car can go from rest to 32.0 m/s in 3.88 s. The same car can come to a full stop from that speed in 4.14 s. What is the ratio of the magnitude of the starting acceleration to the stopping acceleration? 6) An object of weight W is in freefall close to the surface of Earth. The magnitude of the force that the object exerts on Earth is W. W. E) W. 1) 2) 3) 4) 5) 6) 1

2 7) The figure shows an acceleration-versus-force graph for three objects pulled by wires. If the mass of object 2 is 36 kg, what are the masses of objects 1 and 3? 7) 8) In a collision between a huge SUV and a small hybrid car, the SUV exerts a larger force on the hybrid than the hybrid exerts on the SUV. 9) As shown in the figure, a woman is straining to lift a large crate, but without success because it is too heavy. We denote the forces on the crate as follows: P is the magnitude of the upward force being exerted on the crate by the person, C is the magnitude of the vertical contact force on the crate by the floor, and W is the weight of the crate. How are the magnitudes of these forces related while the person is trying unsuccessfully to lift the crate? 8) 9) P C W P C P C W P C W 10) A 200-g hockey puck is launched at an initial speed of 16 m/s up a metal ramp that is inclined at a 30 angle. The coefficients of static and kinetic friction between the hockey puck and the metal ramp are µs = 0.40 and µk = 0.30, respectively. What vertical height does the puck reach above its starting point? 11) A projectile is fired from ground level at an angle above the horizontal on an airless planet where g = 10.0 m/s2. The initial x and y components of its velocity are 86.6 m/s and 50.0 m/s respectively. How long after firing does it take before the projectile hits the level ground? 12) A 3.0-kg and a 5.0-kg box rest side-by-side on a smooth, level floor. A horizontal force of 32 N is applied to the 5.0-kg box pushing it against the 3.0-kg box, and, as a result, both boxes slide along the floor. How hard do the two boxes push against each other? E) 10) 11) 12) 2

3 13) Two small balls, A and B, attract each other gravitationally with a force of magnitude F. If we now double both masses and the separation of the balls, what will now be the magnitude of the attractive force on each one? F F F F E) F 14) From what height above the surface of the earth should an object be dropped to initially experience an acceleration of 0.54g? (G = N m2/kg2, Mearth = kg, Rearth = m) 15) Satellite A has twice the mass of satellite B, and moves at the same orbital distance from Earth as satellite B. Compare the speeds of the two satellites. E) 16) Which of the following quantities are units of momentum? (There could be more than one correct choice.) kg m2/s2 E) 17) In a police ballistics test, a 10.0-g bullet moving at 300 m/s is fired into a 1.00-kg block at rest. The bullet goes through the block almost instantaneously and emerges with 50.0% of its original speed. What is the speed of the block just after the bullet emerges? 18) A stone is released from rest at a height h at the left side of a loop-the-loop, as shown in the figure. There is no appreciable friction from the track or from air resistance. If the radius of the loop is R, what is the minimum height h for which the stone will not fall off the track at the top of the loop? 13) 14) 15) 16) 17) 18) R R 2R R E) R 3

4 19) A person carries a 25.0-N rock through the path shown in the figure, starting at point A and ending at point B. The total time from A to B is 1.50 min. How much work did gravity do on the rock between A and B? 19) E) 20) A baseball is hit with a bat and, as a result, its direction is completely reversed and its speed is doubled. If the actual contact with the bat lasts 0.45 s, what is the ratio of the magnitude of the average acceleration of the ball to its original speed? 2.2 s s s s-1 20) 21) A block is on a frictionless table, on earth. The block accelerates at 3.0 m/s 2 when a 20 N horizontal force is applied to it. The block and table are set up on the Moon where the acceleration due to gravity is 1.62 m/s 2. The weight of the block on the Moon is closest to E) 21) 22) 22) 23) Let the orbital radius of a planet be R and let the orbital period of the planet be T. What quantity is constant for all planets orbiting the sun, assuming circular orbits? T/R T2/R T/R2 T3/R2 E) T2/R3 23) 24) 24) 25) Two cyclists who weigh the same and have identical bicycles ride up the same mountain, both starting at the same time. Joe rides straight up the mountain, and Bob rides up the longer road that has a lower grade. Joe gets to the top before Bob. Ignoring friction and wind resistance, which one of the following statements is true? The amount of work done by Joe is greater than the amount of work done by Bob, and the average power exerted by Joe is greater than that of Bob. The average power exerted by Bob and Joe was the same, but Joe exerted more work in getting there. Bob and Joe exerted the same amount of work, and the average power of each cyclist was also the same. The amount of work done by Joe is equal to the amount of work done by Bob, but the average power exerted by Joe is greater than that of Bob. 26) A runner ran the marathon (approximately 42.0 km) in 2 hours and 57 min. What was the average speed of the runner in m/s? 25) 26) 4

5 27) A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his hands equals his weight, what happens to the fireman? E) 28) An object slides on a level floor. It slows and comes to a stop with a constant acceleration of magnitude 2.4 m/s2. What is the coefficient of kinetic friction between the object and the floor? 29) If you swing a bucket of water fast enough in a vertical circle, at the highest point the water does not spill out. This happens because an outward force balances the pull of gravity on the water. 30) Consider two less-than-desirable options. In the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. In the second option you are driving 30 mph and crash head-on into a stationary brick wall. In neither case does your car bounce back from the thing it hits, and the collision time is the same in both cases. Which of these two situations would result in the greater impact force on your car? 27) 28) 29) 30) 5