Final answer:
The microwave in a house turns on due to nuclear energy from a power plant. Microwaves are a type of electromagnetic radiation used in ovens to heat food by agitating water molecules.
Step-by-step explanation:
The energy produced in a nuclear power plant that allows a microwave in a house to turn on originates from the nucleus of an atom and is known as nuclear energy. A microwave oven works by producing electromagnetic radiation, specifically in the radio portion of the spectrum, which is absorbed by water molecules in food. The absorption of these microwave photons increases the molecules' rotational energies, which in turn heats the food.
It is interesting to note that microwaves can be produced by atoms and molecules through thermal agitation. Also, less exotic but practical amplifiers in microwave ovens use a magnetic field to contain oscillating electrons, which generate the microwaves sent into the oven. This principle is the basis for the hopes of clean energy sources like thermonuclear fusion, leveraged in advanced devices such as the tokamak.