Unit and symbol of centigrade temperature What are the differences

Unit and symbol of centigrade temperature What are the differences

Anders Celsius (1701-1744) was a Swede. At that time, many people in the world had different temperature standards. He also built one: when the water freezes, it is 100 degrees, when it boils, it is 0 degrees. The middle part is divided into 100 parts, and one part is one degree. In this way, the higher the temperature of the water is, the smaller the reading is. It is very inconvenient

Physical symbol, unit, unit symbol and meaning of centigrade temperature

Physical compliance: ° C
Unit: centigrade
Meaning: at a standard atmospheric pressure, the ice water mixture of pure water is recorded as 0 ° C
The boiling point is recorded at 100 ° C

With regard to electrical power,
There are three bulbs L1 "36V 40W" L2 "110V 40W" L3 "220V 40W"; (2) if three bulbs are connected in series in the circuit, which lamp will be on? (3) if three bulbs are connected in parallel in the circuit, which lamp will be on?

The series circuit current is equal, the resistance of L3 is the largest, so L3 is the brightest, the parallel voltage is equal, the smaller the resistance is, the brighter it is, so L1 resistance is the smallest and brightest

Can electric work w = uit = Pt, electric power P = UI = I & sup2; r = u & sup2 / r all be calculated? If so, how to choose the right formula?
Or how to choose the right formula~

Electric work w = uit = Pt electric power P = UI any case, P = I & sup2; r = u & sup2. / r only in pure resistance circuit (all electrical appliances in the circuit only heat), this formula does not hold when there is a motor, that is p ≠ I & sup2; R ≠ U & sup2. / R