Question

Calculate power disspated by the element of an electric fire (heater) of resistance 30 ohms when a

current of 10 amps flows in it. if is on for 30 hours in a week determine the energy used. determine the weekly cost of energy if eletricity costs K 13 per unit​

Answer 1

Weekly cost = K 8,190

Step-by-step explanation:

Given the following data;

Resistance, R = 30 Ohms

Current, I = 10 Amps

Time, t = 30 hours

Cost = K13

I. To find the power dissipated;

Power = current² * resistance

Power = 10² * 30

Power = 100 * 30

Power = 3000 Watts

II. To find the energy consumption;

Energy = power * time

Energy = 3000 * 30

Energy = 90,000 Watt-hour = 90 KWh (1 Kilowatts is equal to 1000 watts).

III. To find the weekly cost;

Daily cost = Energy consumption * cost

Daily cost = 90 * 13

Daily cost = K 1170

Therefore, weekly cost = 1170 * 7

Weekly cost = K 8,190