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If a man increase his speed by 2m/s, his...

If a man increase his speed by 2m/s, his K.E. is doubled, the original speed of the man is

A

`(1+2sqrt2)m//s`

B

4m/s

C

`(2+2sqrt2)` m/s

D

`(2+sqrt2)` m/s

Text Solution

Verified by Experts

The correct Answer is:
C
Initial kinetic energy `E=(1)/(2)mv^(2) " "` …(i)
Final kinetic energy `2E=(1)/(2)m(v+2)^(2) " "` …(ii)
by solving equation (i) and (ii) we get
`v=(2+2sqrt(2))m//s`
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