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प्रश्न
An electric iron is rated 220 V, 2 kW. If the iron is used for 3h daily find the cost of running it for one week if it costs ₹ 4.25 per kWh.
उत्तर
Given,
Power (P) = 2 kW,
Voltage (V) = 220V
Time (t) = 7 x 3 = 21 h
From relation,
E = P x t
Substituting the values in the formula above, we get,
E = 2 x 21 = 42 per kWh
Cost for 1 kWh of energy = ₹ 4.25
Total cost for 42kWh of energy = 4.25 x 42 = ₹ 178.50
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