Question

2. A body of mass 2 kg is thrown up vertically with kinetic
energy of 490 J. The height at which the kinetic energy
of the body becomes half of its original value is​

Answer 1

K.E will be converted into potential energy.

So,

1/2 mv² = m × g × h

Given , K.E = 490 J

mass, m = 2 kg

Half of kinetic energy = 490/2 = 245 J

245 = m × g × h

245 = 2 × 9.8 × h

h = 245 / 19.6

h = 12.5 m

Answer 12.5 m