The regulator can be used to change the amount of heat generated by changing the input voltage and current.
The amount of heat is proportional to the square of the voltage and proportional to the square of the current.
When the voltage becomes 1/2 of the original, the amount of heat becomes 1/4.
When the current becomes 1/2 of the original, the amount of heat becomes 1/4.
How to verify high quality electric heating tube
The most intuitive way to verify the advantages and disadvantages of the electric heating tube is to clean the surface of the electric heating tube first, then turn on the AC 220V power supply, dry it in the air, turn off the surface after it turns red, and then wipe it off with a napkin after the electric heating tube is completely cooled. There should be no black oxidized powder on the white paper (not reacted with oxygen in the air), which is described as a high quality electric heating tube.
The correct formula is:
C (specific heat capacity of the substance to be heated) *M (total mass of substance to be heated) *T (temperature difference) = P (power) * T (time)