PART A: Multiple Choice [13 marks] 1. A race car completes exactly 10 laps around an oval track. Which of the following pairs of quantities concerning its motion would both have values of zero? a. displacement, average speed b. distance, average speed average speed, average velocity d. displacement, average velocity e. average speed, average acceleration 2. The free-body diagram of a block being pushed up a rough an inclined ramp is best represented by B C D E FN Fx/ a. A d. D b. B e. E C 3. An object is travelling north and slowing down. The directions associated with the object's velocity and acceleration, respectively, are a. [S], [N] d. [S], [S] b. [N], [S] e. zero, [S] c. [N], [N] 4. An object has two forces acting on it: 8.4 N [S] and 7.5 N [E]. The magnitude of the net force is 16 N d. 1.3 x 10' N b. 0.9 N e. 11 N . 4.0 N 5. For an object travelling with "uniform circular motion," its acceleration is a. zero because the speed is constant b. magnitude is constant but direction is constantly changing C. directed toward the centre of the circle d. changing in magnitude depending on its position in the circle e. directed outward from the centre of the circle 6. A student lifts a 1.30-kg book from her bag on the floor to her desk 1.00 m above the floor. How much work does gravity do on the book? a. +12.7 J -13.0 J b. -12.7 J e. +13.0 J -0.133 J 7. A 102-g sparrow flying at 12.3 m/s wishes to have equal kinetic and gravitational potential energies. The height that will accomplish this is a. 0.315 m d. 1.13 m b. 0.628 m e. 7.72 m c. 0.787 m 8. A 1.5-kg bird is flying west at a velocity of 18 m/s [220 above the horizontal]. The horizontal component of its momentum is a. 17 kg.m/s [E] d. 25 kg.m/s [W] b. 10 m/s [W] (2 significant digits) e. 6.7 kg.m/s [W] c. 17 m/s [W] 9. A car with a mass of 1800 kg slows from 42 km/h [E] to 28 km/h [E]. The impulse from the brakes is a. 7.0 x 10' N.s [W] d. 2.5 x 10' N.s [W] b. 2.1 x10* N.s [E] e. 2.1 x 10' N.s [W] . 2.5 x 10' N.s [E]10. A student exerts a force of 12 N to compress a spring 2.54 cm. The force constant for the spring is a. 0.30 N/m d. 4.7 x 10' N/m b. 15 N/m e. 31 N/m c. 4.7 N/m 11. Earth's mass is 5.98 x 10"* kg. Calculate the value of gat a point 4.8 x 10' km from the centre of Earth. a. 9.8 x 10"' N/kg d. 1.7 x 10' N/kg b. 8.3 x 10' N/kg e. 9.8 x 10' N/kg C. 1.7 x 10"' N/kg 12. A 722-kg satellite is in circular orbit 7380 km above the surface of Earth (M = 5.98 x 10* kg). The gravitational force acting on the satellite is a. 1.52 x 10' N d. 7.33 N b. 5.29 x 10' N e. 7.08 x 10' N C. 5.29 x 10' N 13. Two charged spheres are 15.00 cm apart. One sphere has a charge of 5.50 x 10" C and the other sphere has a charge of 2.50 x 10 * C. Assuming &= 9.00 x 10'N . m /C', the electric force between the two spheres is a. 5.50 x 10' N d. 1.81 x 10 N b. 5.50 x 10 N e. 6.80 x 10 # N C. 3.44 x 10-20 N