There are several products that perform quite strangely when heated in a microwave oven. The strangest probably is water. There have been many experiments done with microwave ovens, under the ruse of microwave fun. Some of these though have proved how the microwave oven can have a strange effect on them.
Water can get past boiling point when heated in a microwave oven, but without showing any signs of boiling. This generally happens when a new cup is used or a ceramic container. These containers generally have smooth sides with no scratches or cracks in them and this is why the water shows no signs of boiling. If there are no bubbles present in the water or anywhere where air can get trapped within the container, such as cracks or scratch marks, the water when heated in a microwave will not release the energy build up within its molecules.
This process only occurs when the water is heated beyond one hundred degrees centigrade and is called superheating. The water gives the appearance of of just being warmed through, but the energy absorbed within makes it very unstable and the result is explosive when another substance is or object is added to the water. This puts air into the water and in a split second the water boils rapidly releasing a cloud of steam and bubbling out of the container. This has led to people seriously scolding themselves. It is recommended that you put a wooden stick in the cup with the water whilst heating it in your microwave oven.
Putting eggs your microwave oven with the shell on, in attempt to boil them is a definite no. The problem with eggs is that they have a high water content and therefore when microwaved there is build of steam within the egg and after several minutes the result is a massive explosion, which can blow open the microwave oven and completely wreck your microwave. If it doesn't wreck your microwave the resulting mess inside takes a complete age to clean off.
Putting light bulbs or strings of christmas tree lights in microwaves is another extremely dangerous and potently deadly thing to do as the bulbs explode after a short period of time, but the effect is very dramatic and the light show can be quite spectacular.
Bought you by Rossgo of http://www.everythingmicrowaves.com