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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: andysalter on September 09, 2013, 10:20:53 pm

Title: Unit 1/2 momentum question
Post by: andysalter on September 09, 2013, 10:20:53 pm
In a game of snooker a player hit's a 0.2 kg ball with the cue, exerting a force of 40N on the ball for 12 milliseconds.

a) What impulse is exerted on the ball?

I = f x t = 40 (in newtons) x 0.12 (in seconds) = 4.8 Ns    the answer says 0.48 Ns, what did I do wrong?

b) What is the change in momentum of the ball?

Newton's 1st law? Final momentum = initial momentum
therefore momentum = 4.8 kg ms-1     answer says 0.48 kg ms-1

c) With what velocity will the ball leave the cue?

I = m x V  =>  V = I / m  =   4.8 / 0.2 = 24 ms-1    answer says 2.4 ms-1


all the answers are the same as mine just divided by 10... where did I need to do that?

Title: Re: Unit 1/2 momentum question
Post by: Professor Polonsky on September 09, 2013, 10:22:29 pm
12 ms = 0.012 s

That's all.
Title: Re: Unit 1/2 momentum question
Post by: andysalter on September 09, 2013, 10:27:24 pm
hahahaha I feel stupid now, thanks  ;D
Title: Re: Unit 1/2 momentum question
Post by: Guest on September 15, 2013, 09:41:05 am
Time conversions - notorious for tripping Physics students over