Calculating Momentum Change of a Snooker Ball Collision

[Crosshash]

Homework Statement

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)

Homework Equations

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.

Thanks

 

[tiny-tim]

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.

Hi Crosshash!

You're misreading the question … the ball goes forward and back along the same line!

 

[Crosshash]

Hi Crosshash!

You're misreading the question … the ball goes forward and back along the same line!

argh! you're kidding me? I've been stuck on this question for almost 30 minutes and it's that simple!?

I thought it deflects off the side at a right angle :P

I get the right answer now, thankyou!

 

[robertm]

Now if you could just figure out what a snooker is