. If we know the magnitude and direction of the acceleration acting on a body of given mass, Newton's second law allows us to calculate its A) Position vector B) Velocity vector C) Acceleration vector D) Force vector 2. The force of gravitational attraction upon a body is called its A) Mass B) Weight C) Volume D) Acceleration 3. When your car travels around a sharp curve, you feel as if you are flung sideways because A) you continue moving in a straight line B) a centripetal force is acting on you C) the car exerts an outward force on you D) of gravity 4. A constant force of 8.0 N is exerted for 4.0 s on a 16-kg object initially at rest. The change in speed of this object will be: A) 0.5 m/s B) 2 m/s C) 4 m/s D) 8 m/s E) 32 m/s 5. A car tows a 2000 kg trailer up a 20o incline with steady speed. What force does the car exert on the trailer? A) not enough information B) 680 N C) 1900 N D) 6700 N E) 18400 N 6.. How much force is on a .5 m string, attached to a 2 kg mass which is moving on a circular path at 21 m/s? A) 61 N B) 84 N C) 176 N D) 902 N E) 1764 N 7. You are traveling at 30 mph (13.4 m/s) and you hit a concrete wall. Your airbag deploys, bringing you to a stop in a distance of 30 cm. Assume your mass is 75 kg. What is the force of your body mass on the airbag, in bringing you to a stop? A) 603 N B) 1125 N C) 8080 N D) 22,400 N E) 1,125,000 N 8. What is the coefficient of friction if a block slides down an incline of 45o at a constant velocity? A) .1 B) .2 C) .4 D) .7 E) 1.0 9. An automobile moves on a level horizontal road in a circle of radius 30 m. The coefficient of friction between tires and road is 0.50. The maximum speed with which this car can round this curve is: A) 3.0 m/s B) 4.9 m/s C) 9.8 m/s D) 12 m/s E) 13 m/s 10. Two masses are set up as is shown below (just like in lab). The 2.8 kg mass glides friction-free horizontally, pulled to the right by the hanging mass of 3.5 kg. What is the acceleration of the 2.8 kg mass? A) 12.3 m/s2 B) 9.8m/s2 C) 7.6 m/s2 D) 5.4 m/s2 E) 4.4 m/s2 11. Which requires more work, increasing a car's speed from 0 mph to 30 mph or from 50 mph to 60 mph? A) 0 mph to 30 mph B) 50 mph to 60 mph C) It is the same in both cases. 12. Two cyclists weigh the same, have identical bicycles, and ride up the same mountain with 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. Which statement below is true? A) The amount of work done by Joe equals the amount of work done by Bob, but the average power exerted by Joe is greater than that of Bob. B) The amount of work done by Joe is greater than the work done by Bob, and the average power exerted by Joe is greater than that of Bob. C) Bob and Joe exert the same amount of work, and the average power of each is also the same. D) The average power exerted by Bob and Joe was the same, but Joe exerted more work in getting there.

13. Jill does twice as much work as Jack does and in half the time. Jill's power output is A) the same as Jack's power output. B) one-fourth as much as Jack's power output. C) one-half as much as Jack's power output. D) twice Jack's power output. E) four times Jack's power output. 14. It requires 0.30 kJ of work to fully drive a stake into the ground. If the average resistive force on the stake by the ground is 828 N, how long is the stake? A) 0.36 m B) 0.23 m C) 0.31 m D) 0.41 m 15. A rock falls from a vertical cliff that is 4.0 m tall and experiences no significant air resistance as it falls. At what speed will its gravitational potential energy (relative to the base of the cliff) be equal to its kinetic energy? A) 3.1 m/s B) 4.4 m/s C) 6.3 m/s D) 8.9 m/s E) 13 m/s 16. A 1500-kg car accelerates from rest to 25 m/s in 7.0 s. What is the average power delivered by the engine? (1 hp = 746 W) A) 60 hp B) 70 hp C) 80 hp D) 90 hp 17. A 20-ton truck collides with a 1500-lb car and causes a lot of damage to the car. During the collision A) the force on the car due to the collision is much greater than the force on the truck. B) the force on the truck due to the collision is slightly greater than the force on the car. C) the car and the truck have the same magnitude acceleration. D) the force on the truck due to the collision is exactly equal to the force on the car. 18. The momentum of an isolated system is conserved A) only in inelastic collisions. B) only in elastic collisions. C) in both elastic and inelastic collisions. 19. A 328-kg car moving at 19.1 m/s in the +x direction hits from behind a second car moving at in the same direction. If the second car has a mass of and a speed of right after the collision, what is the velocity of the first car after this sudden collision? A) 14.0 m/s B) 18.2 m/s C) 24.2 m/s D) -14.0 m/s 20. A golf club exerts an average horizontal force of 1000 N on a 0.045-kg golf ball that is initially at rest on the tee. The club is in contact with the ball for 1.8 ms. What is the speed of the golf ball just as it leaves the tee?

A) 30 m/s B) 35 m/s C) 40 m/s D) 45 m/s E) 50 m/s