A block slides along a smooth straight groove

PHYSICS · Single correct · CBSE · Physics · Work, Energy and Power · Work, Energy and Power

Problem

1\,\text{kg}

block slides along a smooth straight groove. A position-dependent horizontal force given by

F=6x^{2}+2x

(in newtons) acts in the direction of motion, where

x

is in metres measured from the starting point. The block is released from rest at

x=0

. At what displacement will its speed first reach

10\,\text{m s}^{-1}

? (a)

3.0\,\text{m}

(b)

2.5\,\text{m}

(c)

2.8\,\text{m}

(d)

3.5\,\text{m}