Q. 29 D5.0( 7 Votes )
Calculate the cost of operating a heater of 500 W for 20 hours at the rate of ₹ 3.90 per unit.
Here, Power of heater (P) = 500W = 0.5kW, Time(t) = 20hr
We know that
Energy consumed = P x t = 0.5 X 20
Total cost = 10xcost per unit
Cost per unit = Rs. 3.9 per unit
Therefore, total cost = 10 x 3.9 = Rs 39
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