Physicshard · Past Paper
A house has five 40W lamps and two 100W fans. If everything runs for 10 hours a day, calculate the cost for April (30 days) at Rs 8 per unit.
ARs 960
BRs 800
CRs 1200
DRs 480
✓ Correct Answer: A — Rs 960
Total Power = (5*40)+(2*100) = 400W = 0.4kW. Energy/month = 0.4 * 10 * 30 = 120 units. Cost = 120 * 8 = Rs 960.
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