Why does microwaving continuously for sixty seconds heat food so much more effectively than two consecutive thirty-second cycles?

Question

I noticed that my tea tends to be much hotter when I microwave it continuously than when I take it out half-way through. This result seems to be consistent regardless of material. Even if I open the microwave just for a quick second, whatever I’m microwaving needs significantly more time to heat. Why is this?

In: Physics

Answer 1

The heating element in your microwave takes up to ten seconds to get to full power, and you’ll want to leave the door closed for a few seconds after it beeps to give the element time to cool down and stop sending radiation everywhere.

Also, microwaves typically have hot spots and cold spots, and if your drink doesn’t stumble into a hot spot, while the heating element is hot, during its time in the box, it will be much colder because it absorbed less energy.