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A body is resting on a plane inclined at angle 30° to horizontal. What force would be required to slide it down, if the coefficient of friction between body and plane is 0.3?

A body is resting on a plane inclined at angle 30° to horizontal. What force would be required to slide it down, if the coefficient of friction between body and plane is 0.3? Correct Answer Zero

Concept:

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​For the body to be sliding down on an inclined plane,

mg sinθ > μR

i.e. mg sinθ > μ mg cosθ

by cancelling "m" term from both sides we will get,

tanθ > μ      

Calculation:

Given:

θ = 30°,  μ = 0.3

∴ tan 30 > 0.3

0.577 > 0.3

So there is no force required to slide it down. It will slide down due to its own weight.

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