The rated voltage of electric iron is 220 V, the resistance working under the rated voltage is 1210 Ω, the rated power is calculated, and how much heat is there after passing through 10 minutes under the rated voltage?

The rated voltage of electric iron is 220 V, the resistance working under the rated voltage is 1210 Ω, the rated power is calculated, and how much heat is there after passing through 10 minutes under the rated voltage?

Power P = voltage U × U / resistance
So p = 40W
Heat q = Pt = 40 × (10 × 60 seconds) = 24000 joules!

An electric iron marked with 200V 110W is operated under rated voltage to calculate the power consumption for 10min
The answer given is 66000j. I don't know how to get a formula

t=10min=600s
Power consumption in 10 min: w = Pt = 110 × 600 = 66000 (J)
A: slightly

Electric soldering irons are all marked with "220 V 60 W". They all work by means of current thermal effect. How much electric energy is consumed by its resistance and its normal operation for one hour?

Resistance R = u & # 178 / P = 220 & # 178 / 60 = 806.7 Ω
Power consumption for one hour of operation = 0.06kw × 1H = 0.06kwh (i.e. 0.06kwh)

An electric lamp marked with 220v100w works normally for 40 hours, and the power consumption is

w=pt=100*40