Why does a toaster oven require more time to toast 2 pieces of bread vs 1?

Question

What’s the science? Same rack, same elements heating, same temp, single cooking system. The timer adds additional time for every additional piece of bread gettin a tan.

In: 1

Answer 1

This has to deal with the concept of thermal mass. The more material you need to heat, the more energy it takes. As a thought experiment, instead of bread, think about pieces of bread shaped ice. If you stick stick two pieces of “ice bread” into a toaster, it should take longer for it to all melt compared to one piece. Now, actual bread doesn’t take all that much to toast, so the added time isn’t nearly as much, but the same principle applies.