The charge that flows through the shower in 300 seconds is 18000C. The electric shower has a power of 13.8 kW. Calculate the resistance of the heating element in the shower.
Firstly, we want to define what information we know from the question: ∆Q = 18000C; ∆t = 300s, P = 13.8kW
Therefore, to calculate the resistance we can use the power equation, P=I2R, and calculate the current from: change in charge/change in time.
Current, I = ∆Q /∆t Substituting into this equation the known values: I = 18000/300 = 60A
Now, using the power equation: P = 13800 = (602)R Rearranging this to calculate resistance, R = 13800/3600 = 3.83 Ohms
