Microwave Plate Absorption

[Stevo1684]

Do microwave plates (turntables) absorb a significant amount of radiation? If so, would running a microwave without a plate increase reflection to the magnetron and also (significantly) increase the amount of leaked radiation? Would the same occur with a plate that is smaller than the original?

 

[BradtheRad]

The glass turntable is Borosilicate, a formulation made to resist microwave penetration.

The turntable rotates food so it heats evenly. 'Hot' spots develop at places where microwaves concentrate.

Instructions advise us to run the oven with food or at least a cup of water inside.
The microwaves reflect around inside until absorbed. Dangerous levels of heat can build, or sparks. An internet article states that the waves can reach the magnetron, damaging it.