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TopNewestSince normal( Between block and wedge) is not a dissipative force hence net work done by it on the system is zero.

Now the lower wedge is getting velocity because of the normal force hence it is doing positive work on the wedge , since net work is zero it implies normal force does negative work on the block.

Ans) Negative

Another way to analyse the FBD of the block

The normal force is making an angle \theta with the positive y-axis and the block's displacement has two components one perpendicular to block and one along the -x axis. So work done in first component is zero and work done in second component is -Nxsin(\theta) ( The angle between normal and displacement(x) is 90+\theta)

It is clear work done is negative.

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Yes You are Right Here..!! Kudos..!!

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Best of luck Bhaiya for Sunday. I am sure U will get AIR 1. \(\ddot\smile\)

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If by chance I would get a rank just under 100 I would be over the moon and you are talking about 1 Ha Ha Ha.

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Bhiya Can U give me ur Email ID ?

Please Respond.

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@Ronak Agarwal -please give me link, i cant see any new mechanics problems by you?

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W=F.Swhen force is constant.As clearly seen from diagram,angle b/w force and displacement is 90.

Hence, work done is 0

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@Akhil Bansal I am sorry but the angle between force and displacement here is not 90..!!

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Can you see this ?

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Comment deleted Jul 08, 2015

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Then how come wedge is getting the kinetic energy??

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the weight of the block is divided into two components. one gives it velocity along the wedge and the other is perpendicular onto the wedge.

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weight

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weight of wedge can't do work on wedge as its displacement is perpendicular to the force and weight of block cant do work on wedge either as it is not acting on wedge it is acting on block..!!!

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