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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. – Ronak Agarwal · 2 years, 2 months ago

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– Rohit Gupta · 2 years, 2 months ago

Yes You are Right Here..!! Kudos..!!Log in to reply

– Rajdeep Dhingra · 2 years, 2 months ago

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

– Ronak Agarwal · 2 years, 2 months ago

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.Log in to reply

Please Respond. – Rajdeep Dhingra · 2 years, 2 months ago

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– Ronak Agarwal · 2 years, 2 months ago

The problems are a little easy and it seems like lol and troll ( when he says he himself has not solved )Log in to reply

– Rohit Gupta · 2 years, 2 months ago

My Aim here is not to put such problems that no one is able to solve...But to put conceptual problems....And I have never claim that i was not able to solve them.. Problems are not grt There Solutions Are..!!Log in to reply

– Ronak Agarwal · 2 years, 2 months ago

Sorry I was not talking about you, Rohit Sir Check the link Given by Rajdeep, there a child has created some problems I was talking about him,these conceptual problems are good SirLog in to reply

– Rohit Gupta · 2 years, 2 months ago

Opps My bad... Sry for misunderstanding..!! And all the best for you Advance test..!!Log in to reply

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– Ronak Agarwal · 2 years, 2 months ago

But you solved all my mechanics problems very very easily I see you in solvers list of my every problem, It simply proves you are quite intelligent in physics, you see I have recently released part 4 of my challenges in mechanics.Log in to reply

@Ronak Agarwal -please give me link, i cant see any new mechanics problems by you? – Mvs Saketh · 2 years, 2 months ago

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– Ronak Agarwal · 2 years, 2 months ago

I thought you already saw it , anyways click on my profile.Log in to reply

– Rajdeep Dhingra · 2 years, 2 months ago

Thank You Bhiya. Your problems are great! You would surely get AIR 1.Log in to reply

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

Hence, work done is 0 – Akhil Bansal · 2 years ago

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@Akhil Bansal I am sorry but the angle between force and displacement here is not 90..!! – Rohit Gupta · 2 years ago

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this ? – Rajdeep Dhingra · 2 years ago

Can you seeLog in to reply

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– Rohit Gupta · 2 years, 2 months ago

Then how come wedge is getting the kinetic energy??Log in to reply

– Ansh Bhatt · 2 years, 2 months ago

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.Log in to reply

– Rajdeep Dhingra · 2 years, 2 months ago

Even I thought the same.Log in to reply

– Rajdeep Dhingra · 2 years, 2 months ago

weightLog in to reply

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..!!! – Rohit Gupta · 2 years, 2 months ago

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– Ansh Bhatt · 2 years, 2 months ago

sir i wrote in my comment above, if it is wrong then i don't know the answer but one component of the weight of the block will act on the wedge.Log in to reply

– Rajdeep Dhingra · 2 years, 2 months ago

Then sir please tell.Log in to reply