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- #1

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- #1

- Mar 1, 2012

- 935

show your work on this problem, please

- Jan 30, 2018

- 756

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- #4

m=0.4kg, u=3m/s, coefficient of friction =0.3show your work on this problem, please

By using Newtons law

F=m×a

-0.3×4=0.4a

a=-3m/s^2,

By using v^2=u^2+2as, v=2.05m/s when the ball hits the cushion

The speed decreases by 20%, so 2.05×0.8=1.64m/s. Again using v^2=u^2+2as, I get s=0.25m

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- #5

Oh sorry I had done a silly mistake. So initial velocity is 3 and when it hits the cushion, the final velocity is 2.05 m/s , this is reduced by 20% so now u= 1.64 m/s and v=0 ( as the ball stops) so the distance will be 0.448mshow your work on this problem, please

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- #6

Thanks! I could work out the solution.rollswith only a slight amount of sliding. The coefficient of friction only applies to the sliding. To answer this you would have to know what part of the motion was sliding and I see no way to determine that.

- Jan 30, 2018

- 756

I am glad. How did you handle the "rolling versus sliding" problem?

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- #8

I just guessed rolling. Iam still in A levels so probably my textbook doesn't get into so much detail.I am glad. How did you handle the "rolling versus sliding" problem?

- Jan 30, 2018

- 756

If there were pure rolling, there would be NO friction!

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- #10

Yeah you are right.If there were pure rolling, there would be NO friction!