# Problem: A. How many joules of energy does a 100-watt light bulb use per hour? B. How fast would a 70-kg person have to run to have that amount of kinetic energy?

###### FREE Expert Solution

The energy of a light bulb:

$\overline{){\mathbf{E}}{\mathbf{=}}{\mathbf{P}}{\mathbf{t}}}$

The energy of a running person is equal to the kinetic energy of that person, expressed as:

$\overline{){\mathbf{E}}{\mathbf{=}}\frac{\mathbf{1}}{\mathbf{2}}{\mathbf{m}}{{\mathbf{v}}}^{{\mathbf{2}}}}$

###### Problem Details

A. How many joules of energy does a 100-watt light bulb use per hour?

B. How fast would a 70-kg person have to run to have that amount of kinetic energy?