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A pendulum of length 2 m lift at P . Whe...

A pendulum of length 2 m lift at P . When it reaches Q , it losses 10% of its total energy due to air resistance. The velocity at Q is

A

6 m/s

B

1 m/s

C

2 m/s

D

8 m/s

Text Solution

Verified by Experts

The correct Answer is:
A
`(1)/(2)mv^(2)=(0.9)mgh`
`implies v^(2)=2xx0.9xx10xx2=36`
`implies v=6m//s`.
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