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A block of mass 5 kg is initially at res...

A block of mass `5 kg` is initially at rest on a rough horizontal surface. A force of `45 N` acts over a distance of `2 m`. The force of friction acting on the block is `25 N`. The final kinetic energy of the block is

A

40 J

B

90 J

C

50 J

D

140 J

Text Solution

Verified by Experts

The correct Answer is:
A
`Delta K = W , K.E_(f) - 0 = F_("net") S cos theta`.
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