a)Two balls of equal masses undergo and elastic collision on a pool table. The final velocities of the two balls are v1=18m/s [S10W] and v2= 14m/s [S30E]. If the initial velocity of the first ball was w1=16m/s [S15E], what was the initial velocity of the second ball?
b) Evaluate the following statement mathematically - "The two balls underwent a perfectly elastic collision."
p = mv
The Attempt at a Solution
Firstly, I drew out all the given vectors in the questions. Initial velocities in the top half and final velocities in the bottom. Then I established reference directions. I realise that according to the conservation of momentum, the momentum will be equal initially and finally. I apply this to the x and y components of the vectors to form two seperate equations. By solving for the unknown velocity component in each case, I go onto equate them, allowing me to find the value of Theta.
After that, finally, I find the speed. I am not exacly sure how to deal with the last part of the question. Can anyone help to verify my work as well as provide any suggestions to the last part? Help would be very much appreciated!