A body of mass 2 kg is thrown up vertically with K.E. of 490 joule. If the acceleration due to gravity is 9.8 m/s2, then the height at which the K.E. of the body becomes half its original value is given by
12.5 m
Let h is that height at which the kinetic energy of the body becomes half its original value i.e. half of its kinetic energy will convert into potential energy
∴mgh=4902⇒2×9.8×h=4902⇒h=12.5m.