Question
confirm
hile roller-skating, Granny collides with her tiny grandson Ambrose who is at rest Ignoring any friction effects, Ambrose's speed after the collision will be greatest when a. Granny catches him and they both move together. b he and Granny make a bouncing collision, each going in opposite directions. The impulse experienced by a body is equivalent to the body's change in a. impact b momentum c. force d. velocity wo swimmers relax close together on air mattresses in a pool. One swimmer's mass is 48 kg, and the other's mass is 55 kg. If the swimmers push away from each other a. their total momentum triples. b. their momenta are equal but opposite. d. their total momentum doubles their total momentum decreases. A person sitting in a chair with wheels stands up, causing the chair to roll backward across the floor. The momentum of the chair a. was zero when the person got out of the chair and increased while the person sat. b. remained the same. c was zero while stationary and increased when the person stood d. was greatest while the person sat in the chair FIGURE 7-3A same speeds A moving ball collides and sticks together with an identical ball moving in the opposite direction at the same speed as illustrated in FIGURE 7-3A. After collision, the speed of the combined balls will be: a. zero d. the same as before e. one-fourth as large as before b half as large as before twice as large as before c.
Explanation / Answer
1 b) Correct
2 b)correct
3 b)is correct. Optiuon b is correct from conservation of momentum point of view. The initila momentum of the system was zero. Therefore, final momentum of system also has to be zero from conservation of momentum point of view because there is no external force acting on the system. For final momentum to be zero, their momenta have to be equal and opposite.
4 c)is correct
5 a) is correct. This is again coming from conservation of momentum. Initially, the total momentum of the system was zero because both the ball have same mass but equal and opposite speed. Therefore, after the colliion,since the balls stick together,their velocity will be equal the total momentum will be zero .Therefore, answer is zero
