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Assertion: A neddleplaced carefully on t...

Assertion: A neddleplaced carefully on the surface of water may float while a ball of the same material will always sink.
Reason: The buoyancy of an object depends both on the material and the shape of the object.

A

If both assertion and reason are ture and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reson are false.

Text Solution

Verified by Experts

The correct Answer is:
C
A needle placed carefully on the surface of water may float due to surface tension as upward force due to suface tension balances the weight of the needle. But these upward force due to surface tension are very small as compared to weight of ball. Also the weight of liquid displaced by the ball immersed in liquid is less than the weight of the ball. hence ball sinks into the liquid .
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