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A block of mass m is kept on the ground....

A block of mass m is kept on the ground. A vertically upward for F = kt (K is a positive constant) where 't' is in seconds , starts to act on it at t = 0

A

the block looses contact with ground at t = mgK

B

For `0 lt t le (mg)/k` , normal reaction decrease linearly with time but force exerted by body on ground also decreases

C

For `0 lt t le (mg)/k` , normal reaction decrease linearly with time but force exerted by body on ground is a constant

D

At `t=(2mg)/k` , velocity of the body is zero

Text Solution

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The correct Answer is:
A, B, C
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Knowledge Check

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