A running back has 3500 J of kinetic energy and is running at a speed of 8 m/s. Calculate his mass.

KE = 1/2 m*v^2

109.375 mass

To calculate the mass of the running back, we can use the formula for kinetic energy:

Kinetic energy = 1/2 * mass * velocity^2

Given that the kinetic energy is 3500 J and the velocity is 8 m/s, we can rearrange the formula to solve for mass:

mass = (2 * Kinetic energy) / velocity^2

Plugging in the given values, we get:

mass = (2 * 3500 J) / (8 m/s)^2
= 7000 J / 64 m^2/s^2
= 109.375 kg

Therefore, the mass of the running back is approximately 109.375 kg.