Physics

Problem

When a rubber-band is stretched by a distance

x

, it exerts restoring force of magnitude

F = ax + bx^2

where

a

and

b

are constants. The work done in stretching the unstretched rubber-band by

L

is: a.

aL^2 + bL^3

\frac{1}{2}(aL^2 + bL^3)

\frac{aL^2}{2} + \frac{bL^3}{3}

\frac{1}{2}\left(\frac{aL^2}{2} + \frac{bL^3}{3}\right)