The kinetic energy of the body is 16 J and the momentum is 4 kg * m / s. What is body weight?

Ek = 16 J.

p = 4 kg * m / s.

m -?

Kinetic energy Ek is called the energy of motion, because it is determined by the formula: Ek = m * V ^ 2/2, where V is the speed of movement, m is the mass of the body that is moving. Kinetic energy Ek is a scalar physical quantity.

m = 2 * Ek / V ^ 2.

The product of the mass of a body m by the speed of its movement V is called the momentum of the body p: p = m * V. Momentum p is a vector physical quantity directed the same way as the speed of movement of the body V.

V = p / m.

m = 2 * Ek * m ^ 2 / p 2.

m = p ^ 2/2 * Ek.

m = (4 kg * m / s) ^ 2/2 * 16 J = 0.5 kg.

Answer: body weight is m = 0.5 kg.