Safety
A common
misconception is that microwaves can cause cancer.
Microwaves are a form of non-ionizing radiation. This means that this form of radiation does not have the kinetic energy to ionize (liberate an electron or an atom from a particle), and therefore cannot directly damage a DNA structure. Ionizing radiation comes from much higher frequencies in the electromagnetic spectrum.
Why you shouldn't put metal in a microwave:
One property of many metals is that they are really good at reflecting microwaves. This is why the metallic mesh on a microwave's door does not allow any radiation out of the chamber- the wavelength of microwaves are too large to pass through the holes, and they are reflected back into the chamber. When smaller, ungrounded pieces of metal are exposed to microwave radiation, they cause the free electrons on the metals surface to flow to a point, creating a charge. When this charge is great enough to overcome the resistance offered by air as an insulator, the charge will arc to something else (like the walls of the oven).
Microwaves are a form of non-ionizing radiation. This means that this form of radiation does not have the kinetic energy to ionize (liberate an electron or an atom from a particle), and therefore cannot directly damage a DNA structure. Ionizing radiation comes from much higher frequencies in the electromagnetic spectrum.
Why you shouldn't put metal in a microwave:
One property of many metals is that they are really good at reflecting microwaves. This is why the metallic mesh on a microwave's door does not allow any radiation out of the chamber- the wavelength of microwaves are too large to pass through the holes, and they are reflected back into the chamber. When smaller, ungrounded pieces of metal are exposed to microwave radiation, they cause the free electrons on the metals surface to flow to a point, creating a charge. When this charge is great enough to overcome the resistance offered by air as an insulator, the charge will arc to something else (like the walls of the oven).