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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 ms^(-1)`

B

`1 ms^(-1)`

C

`2 ms^(-1)`

D

`8 ms^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
C
(c ) Gain in KE =Loss in PE
` implies " " (1)/(2)mv^(2)=(0.1)(mgh)`
`:. " " v=sqrt(0.2gh)=sqrt(0.2xx10xx2)=2 ms^(-1)`
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