physics....
posted by kennedy .
Suppose that the inside length of a microwave oven is 30 cm. If the length of a microwave oven is one half of the wavelength of microwaves used by the oven, find the frequency of the microwaves used in the oven.
What is the equation that relates the three of these???

Microwaves travel at the speed of light.
You must have seen this equation before for electromagnetic radiation:
(wavelength) * (frequency) = (speed of light)
Rewrite that as
2*(Microwave length)*(frequency) = 3*10^10 cm/s
Solve for the frequency
f = 5.00^10^8 Hz = 0.5 GHz
Actually, microwave ovens use a higher frequency than that.