Question

1. A loaded gun is dropped on a frozen lake. The gun fires, with the bullet going horizontally in one direction and the gun sliding on the ice in the other direction. The bullet's mass is 0.04 kg, and its speed is 305 m/s. If the gun's mass is 1.8 kg, what is its speed (in m/s)?

______m/s

2. A 37 kg child uses a pogo stick to bounce up and down. The spring constant, k, of the toy equals 8,850 N/m.

(a)By how much would the spring be compressed by the child if she simply balanced herself vertically on the pedals of the stick? (Give your answer in cm.)

_______ cm

_______(b)How much energy (in J) is stored in the spring under this circumstance?

_______ J

3.A 8,900-kg truck runs into the rear of a 1,000-kg car that was stationary. The truck and car are locked together after the collision and move with speed 5 m/s. Compute how much kinetic energy was "lost" in this inelastic collision.
________________J

5.A spring is stretched by an initial amount from its relaxed state. If the spring is then stretched by three times that amount from its relaxed state, by what factor does the amount of mechanical energy stored in the spring change?

PE_final

PE_initial

6.A sprinter with a mass of 83 kg reaches a speed of 8 m/s during a race. Find the sprinter's linear momentum (in kg · m/s). (Enter the magnitude.)

_________ kg · m/s

Answer 1