Cardboard one would just blacken on the edges. Styrofoam would melt and probably catch fire.
it melts
If there was no feedback in an oven system, it would keep getting hotter until it melted, exploded, or was turned off.
If you place a potato on an piece of unprinted paper in the microwave oven, the potato would heat up, the paper would not.
Putting metal in the microwave can cause a fire to happen.
The roast I just put in the oven would be ruined in about an hour.
You will have a slightly higher utility bill
* milk carton * mixer * melon baller * microwave oven * mugs
its a loaf
1500 Watt.
Nothing, rubber is unaffected at 212 degrees Fahrenheit. The worst thing that could happen is that the water in the bowl could boil violently after a while (not that it will blow the door off your microwave oven).
It will melt
not usually, but it does happen