Right- the difference between cooking a chicken nugget and a chicken.
I suspect this might be true in a (theoretical) perfectly insulated oven, in which the only loss/transfer of heat was to the muffins. But in such an oven, the heat wouldn’t come back on hardly at all once the oven had reached its set operating temperature, and the difference between one and two pans would be negligible.
In a microwave oven, the energy is transferred more-or-less directly to the food, so that twice as much food does come closer to requiring twice as much time; but that’s not the way a conventional oven works.
All of the above is my inexpert understanding, about which I am willing to be corrected.
The heating coils turn on in response to lowered temperature, which is caused by heat loss. Heat loss in an oven happens in two broad ways: 1) Heat is used for chemical reactions required to cook the food or to boil and evaporate liquids, and 2) heat escapes the oven through radiation and convection; turn on an empty oven and you will note that the coils continue to cycle on and off. Ovens are specifically designed to minimize #2 although in my oven (1995 GE Profile electric*) there is some degree of venting; when the contents are smoking it comes out vents in the front.
The amount of heat generated to heat the entire oven to and maintain a specific temperature is much greater than the heat actually needed to cook the food in many cases, including a pan of muffins (Not sure if the same is true of a 22-pound turkey). That is, of the heat needed to raise the temperature to, say, 350F, only a relatively small portion of that heat is used to bake the muffins. Therefore adding a second tray of muffins does not double the heat requirement. I don’t know the numbers but I would bet that heat loss through the walls of the oven exceeds the heat used to actually bake the muffins.
*Yes, BakingWithElectricity.
Cooking or baking is a classic heat transfer / reaction engineering problem for Chemical engineers. In undergraduate Junior or Senior years, the engineering textbooks have the classic problem of calculating the time it needs to bake a potato. Here is a website that talks about the physics/chemistry of the problem : Index
Almost all ovens have the capacity to regulate temperatures in the moderate ranges even when the oven is well loaded and also accounts for heat losses. The time for cooking is determined by heat transfer & reaction kinetics (read Millard reaction for an example of a heat reaction that explains why seasoning enhances flavor) and usually follow the Arrhenius equation. So 10 or 20 nuggets will not make much difference.
Now - if you insert a nail (sterilized of course) in each of the nuggets, you will get done faster perhaps !
It’s called The McNugget Surprise! :eek:
Hmm. Does it involve pan-fried semen?
Finger, toe, or does it matter?
This thread has taken a turn for the gross.
Lots of interesting… nuggets… in this thread. Thank you all 
The surface area to mass ratio of the nuggets won’t change when you add more, so they should take in heat at the same rate no matter how many are in the oven, unless they are packed too close together. That would effectively decrease their surface to mass ratio, so make sure those nuggets are well separated.