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:

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

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?

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Power concept. You can view video lessons to learn Power. Or if you need more Power practice, you can also practice Power practice problems.