Physics

Problem

For a light spring, the restoring force varies with extension according to

F(x)=kx+bx^{2}

, where

k=100\,\text{N m}^{-1}

b=20\,\text{N m}^{-2}

, and

x

is in metres. Calculate the work required to stretch the spring from

x=0.10\,\text{m}

x=0.30\,\text{m}

. a)

4.68\,\text{J}

4.0\,\text{J}

4.2\,\text{J}

6.3\,\text{J}