Science Buddies: "Ask an Expert"

We are testing the strength of a magnet in hot and cold temperatures. The magnet is our constant. In testing the magnet, would it be better to test hot, cold, then hot, and cold again. Or should we test hot, hot, then cold, cold. We will be boiling and freezing the magnet. Our opinion is to alternate so that way if there is any diminishing factors done to the magnet each variable would have an equal chance.
Thank you for your help.
Becky Kirby

Hello Becky,

You are correct. It would be better to “mix up” the order of your hot/cold testing. As you pointed out the magnet strength (or some other factor) might change due to repeated heating/cooling. And alternating the hot/cold cycle would help to average out that effect.

Taking it one step further, you could test hot/cold, hot/cold, cold/hot and cold/hot. That way you'd have both possible heating/cooling orders included.

I hope this helps. Please ask again if you have more questions.

A. Norman