Determine from what height a body weighing 1 kg will fall, if at the moment of its impact on the Earth
Determine from what height a body weighing 1 kg will fall, if at the moment of its impact on the Earth its kinetic energy was equal to 98 J.
m = 1 kg.
g = 9.8 m / s2.
Ek = 98 J.
h -?
When the body falls, the law of conservation of total mechanical energy is valid.
The total mechanical energy of the body is conserved.
The total mechanical energy E is the sum of the potential En and the kinetic energy Ek: E = En + Ek.
At the moment of the beginning of the fall, the total mechanical energy of the body consists only of the potential energy En = m * g * h.
At the moment of impact, the total mechanical energy of the body consists only of kinetic energy Ek = m * V2 / 2.
Ek = m * g * h.
h = Ek / m * g.
h = 98 J / 1 kg * 9.8 m / s2 = 10 m.
Answer: the body fell from a height of h = 10 m.