Question

When a body is projected vertically up from ground, the ratio of its potential to kinetic energies at a height 'h' above
the ground is 3:4. The height above ground at which the ratio of potential to kinetic energies becomes 4:3 is
​

Answer 1

Explanation:

Let in the first case, the total energy at the throwing point be 5E.

KE at a particular height =3E, potential energy at the height =2E

As velocity of thrown is doubled, kinetic energy becomes 4 times.

∴ Total KE at the throwing point 20 E

PE at the same height =2E (will remain same as the previous value) and KE at the same height =18E

KE

PE

=

18E

2E

=

9

1

=1:9.