Question

when a spring is stretched by 2 cm, it stores 100 j of energy . if it is stretched further by 2 cm, the stored energy will be increased by

Answer 1

200 j is the answer,...........

Answer 2

Given:

The stretched spring length x= 2 cm

The energy stored E= 100 J

To find:

The stored energy when again increased

Solution:

As the x=2 cm

The energy stored formula

E=kx²/2

100=0.5×k×2²

k=50

Now when further increase x=4 cm

E=0.5×50×4²

=400J

So the stored energy on increase of length be 400-100=300 J