Two stones one cue
Two billiard balls A and B are located as above. When a player hits the red ball(A) towards the blue ball(B), the two balls collide elastically, and then A and B enter into pockets P and Q, respectively. The masses of the two balls are the same. Which of the following statements is correct? (Ignore the friction and spin of the balls.)
a) At the moment of the collision, the magnitude of the impulse received by each ball is the same.
b) After the collision, B enters into pocket Q faster than A enters into pocket P.
c) The kinetic energy of A before the collision is greater than the sum of the kinetic energies of the two balls after the collision.
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1 solution
A) is true because ball A makes a force on ball B and ball B makes the same force on ball A, as the colission time is the same for both, and impulse (I) depends only on force (F) and how much time (t) the body suffered this force [ I = F / t ]
B) is true but I can't explain why
C) is false because it's a ELASTIC collision and in a elastic colission the energy is aways conserved on the system