Question 20
Electrical Energy and PowerA landlord has eight 40 W electric light bulbs, four 60 W bulbs and two 100 W bulbs in his house. If he has all the points on for five hours daily and if N.E.P.A. charges 5k per unit, his bill for 30 days is
- A.N5.70
- B.N7.23
- C.N3.65
- D.N8.05
- E.N4.50
Show the answer and explanation
Answer: A (N5.70)
Explanation
Total power = 320 + 240 + 200 = 760 W = 0.76 kW. Energy = 0.76 × 5 × 30 = 114 kWh. Cost = 114 × 5k = 570k = N5.70.