Question

how is produced when we rub our hands?

Answer 1

how is produced when we rub our hands ... there's something missing from this question - is it the word "heat" ? If so, then the answer is that rubbing hands together, means that you do mechanical work against the friction between your hands. Some of that work goes into heat. You can find this also with a scarf, as in the thing you put round your neck to keep your neck warm. If you pull the scarf round your neck for a few inches, you'll feel heat on your skin where the scarf has moved. It's the work done against friction between neck and scarf which generates the heat.

Answer 2

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