Household Electricity — Question 1

(a) If an electrical appliance is rated as 60 W - 150 V, it means if the appliance is put on a 150 V supply, it will consume 60 W electrical power (i.e., it will consume 60 J of electrical energy in 1 s).

(b) P = 60 W
V = 150 V

We know P = VI

∴ I = $\dfrac{\text{P}}{\text{V}}$ = $\dfrac{\text{60}}{\text{150}}$ = 0.4 A

So, current of 0.4 A will flow through the appliance when in use.