In: Physics
Energy can be stored in an elastic band by stretching
it.
Let x be the distance over which the band is stretched.
If the force which the band exerts to restore itself to its
original
shape is given by F = ax + bx2
, where a and b are constants,
find work done in stretching the band from x=0 to x=L.
(a) aL+ bL2
(b) (aL2+ bL3)/2
(c) aL2/2+ bL3/3
(d) (aL2/2+ bL3/3)/2.
Infinitesimal Work
done to stretch the rubber band by infinitesimal
length
under the application of force
will be given as,
Integrating above equation over variable from
to
, we will get, the net work done
in stretching the rubber band by length
as,
work done to stretch the rubber band by length of
,
,
Using given expression for force that is
in above integral we will get,
Solving the integrals we get,
So, we get the work done in stretching rubber band from
as,