[thedoc (OP)]

The inner walls of a microwave oven are made of metal; so why does the oven explode when another piece of metal is placed inside it?

Asked by aceng.at

                                        Visit the webpage for the podcast in which this question is answered.
[chapter podcast=1000585 track=14.01.07/Naked_Scientists_Show_14.01.07_1001828.mp3]  ...or Listen to the Answer[/chapter] or [download as MP3]

[hamdani yusuf]

Electroboom tried to answer the question in his video.

Spoiler: show

Unfortunately, no single conclusive and reliable condition is found to predict the occurance of spark in microwave oven. I've also done the experiment myself, but didn't publish it for the lack of interesting finding.