Why does a disc stay stationary while rotating when you pull the plank from under it?

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AdityaDev
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When you put o disc on top of a plank and if you pull the plank, the disc rotates but stays stationary.
Here the friction between the plank and disk produces an unbalanced torque and hence it spins.But this friction should also cause an acceleration in the disc right? Then why does it remain stationary?
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who gived the assumption that it stay stationary? it does not stay stationary at all i think, just apply Newton's law...i'm curios about answers to this question :)
 
GiuseppeR7 said:
who gived the assumption that it stay stationary? it does not stay stationary at all i think, just apply Newton's law...i'm curios about answers to this question :)
Sorry. It doesn't stay stationary. Actually i was thinking about this question. I did not understand it properly.
I got the first two correct but i am still working on Q3.
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ah ok :) what book is that by the way? title and author? thanks!
 
GiuseppeR7 said:
ah ok :) what book is that by the way? title and author? thanks!
You can't buy it. You have to join my coaching institute. The questions are set by some reputed teachers and the book gets updated every year. No particular author. It's called Grand Masters Package.the questions are very difficult.
 
ah ok...thank you :)