A coin is placed on a horizontal platform which undergoes vertical SHM of angular frequency "w". The amplitude of oscillation is gradually increased.the coin will leave contact with the platform for the first time at?

Question

A coin is placed on a horizontal platform which undergoes vertical SHM of  angular frequency "w". The amplitude of oscillation is gradually increased.the coin will leave contact with the platform for the first time at?

parthkohli · Answer

$$\frac{N-mg}{m}=-\omega^2 x$$$$N\ge0 \Rightarrow \text{contact maintained}$$

priyar · Answer

at N=0 there is no contact..right?

parthkohli · Answer

Yes.

priyar · Answer

then why did u include it in the abv. exp?

parthkohli · Answer

Oh dunno why I typed $\ge 0$.

parthkohli · Answer

Yeah, it's just $>0$.

priyar · Answer

ok...give me a min.. lemme try to do this

priyar · Answer

at x= g/w^2 right? btw where have used the fact that amplitude is gradually increasing?

parthkohli · Answer

Nowhere, really. It's like saying we have an inclined slope with a gradually increasing angle, and it asks you to find the angle at which a block begins to slip.

ganeshie8 · Answer

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