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A horizontal plank has a rectangular blo...

A horizontal plank has a rectangular block placed on it. The plank starts oscillating verically and simple harmonically with an amplitude of `40 cm`. The block just losses contact with the plank when the latter is at momentary rest. Then :

A

the period of oscillation is `((2pi)/(5))`

B

the block weighs double its weight, when the plank is at one of the positions of momentary rest.

C

the block weighs 0.5 time its weight when the plank is half way up

D

the block weighs 0.5 time its weight when the plank is halfway down

Text Solution

Verified by Experts

The correct Answer is:
A, B, C
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