A snooker ball of mass 0.350kg hits the side of a snooker table at right angles, and bounces off also at right angles. If its speed before collision is 2.8ms^-1 and its speed after is 2.5ms^-1, calculate the change in its momentum.
(The answer to the question is not 0.105kg ms^-1)
p = mv (well, that's what I've tried answering it with)
The Attempt at a Solution
I'm assuming my method is flawed, but I thought it might be worth using pythagoras to work out the actual (?) velocity.
I got 3.75 but if you do 3.75*0.35 i reach 1.3 which according to the answers in the back of the book are incorrect.
Could someone enlighten me please? I'm really stumped.