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Question
An electrical appliance is rated 1500 W, 250 V. This appliance is connected to 250 V mains. Calculate:
(i) the current drawn,
(ii) the electrical energy consumed in 60 hours,
(iii) the cost of electrical energy consumed at Rs. 2.50 per kWh.
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Solution
(i) Since, W = V × i, But given that W = 1500, V = 250
Current, i = `"W"/"n"`
`= 1500/250 = 6` amperes
(ii) Energy consumed in 60 hours
`= ("Watts" xx "hours")/1000` kWh
`= (1500 xx 60)/1000 = 90` kWh
(iii) Cost of 90 kWh at Rs. 2.50/kWh = Rs. 90 × 2.50 = Rs. 225.00.
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