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A body while sliding went straight down ...

A body while sliding went straight down an incline of `45^(@)` to the horizontal and was subjected to a coefficient of kinetic friction of `0.20.` Starting from rest, hwo long did it take him to reach a speed of `50 km//hr?` (Ignore air resistance and take `h= 10 m//s^(2))`

A

`2.45s`

B

`9.2 s`

C

`1.5xx10^(2)s`

D

`2.0s`

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The correct Answer is:
A
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