Question

A 48-kg boy is running on a track at 6m/s . What is the boys kinetic energy?

Answer 1

Given:
m = 48 kg, the mass of the boy
v = 6 m/s, the boy's running speed

By definition,
 the kinetic energy (KE) of the boy is
KE = (1/2)*m*v²
     = 0.5*(48 kg)*(6 m/s)²
     = 864 J

Answer: 864 J

Answer 2

864 J In order to calculate kinetic energy the mass of the moving body and it's velocity must be known. In this case the mass is 48 kg and the velocity is 6 m/s. The formula for kinetic energy is: Kinetic Energy = 1/2 * (Mass) * (Velocity^2) = 1/2 (48 kg) * ((6 m/s)^2) = 864 kg* (m/s)^2 = 864 J