Two balls having different masses reach the same height when shot into the air f
ID: 1641715 • Letter: T
Question
Two balls having different masses reach the same height when shot into the air from the ground. If there is no air drag, which of the following statement must be true? A) Both balls left the ground with the same speed. B) Both balls left the ground with the same kinetic energy. C) Both balls will have the same gravitational potential energy at the highest point. D) The heavier ball must have left the ground with a greater speed than the lighter ball. E) Both balls have no acceleration at their highest point. The stone in the accompanying figure can be carried from the bottom to the top of a cliff by various paths. Which path requires more work? A) AC B) BC C) ABC D) ABCD E) The work is the same for all of the above paths. A small car collides head-on with a large SUV. Which of the following statement concerning this collision is always correct? A) Both vehicles are acted upon by the same magnitude of average force during the collision. B) The small car is acted upon by a greater magnitude of average force than the SUV. C) The small car is acted upon by a smaller magnitude of average force than the SUV. D) The small car undergoes a greater change in momentum than the SUV. E) The small car undergoes a smaller change in momentum than the SUV. A ball of mass 0.18 kg moving with speed 11.3 m/s collides head-on with an identical stationary ball. (Notice that we do not know the type of collision.) Which of the following quantities can be calculated from this information alone? A) The force each ball exerts on the other. B) The velocity of each ball after the collision. C) Total kinetic energy of both balls after the collision. D) Total momentum of both balls after the collision. E) The momentum of each ball after the collision. A rifle of mass M is initially at rest, but is free to recoil. It fires a bullet of mass m with a velocity relative +v to the ground. After the rifle is fired, its velocity relative to the ground is A) +mv/(m + M). B) -mv/(m + M). C) -mv/M. D) -Mv/m. E) + (m + M)v/M.Explanation / Answer
6) Height Reached only depends on Initial Speed so the only true statment is
A) Both balls left the ground with same speed.
7) The path is not visible but the work done to lift an object to a height is same through any path because the change in energy is the same.So the answer is E) Work is same for all paths.
8) Since there is no net change in momentum the change in momentums of both vehicles is same implies
A) The average force acted on the both vehicles is same
9) In any type of collison the momentum is always conserved. Since we know the initial momentum we can calcuate the final momentum so the correct statement is
D) Total momentum of both balls after collision.
10) From momentum conservation Initial momentum is zero and let the velocity of recoil of gun is Vg. So the equation is MVg + mv = 0 implies Velocity of gun is Vg =
C) -mv/M