Calculate the cost of operating a heater of 500W for 20hours at the rate of? ₹3.90 per unit.
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Given P = 500W = 0.5KW, t = 20hr
We know that
Energy consumed = P × t = 0.5 × 20
= 10KWh
Total cost = 10 × cost per unit
cost per unit = Rs. 3.9 per unit
Therefore, total cost = 10 × 3.9 = Rs. 39
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