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Question
For a heater rated at 4 kW and 220 V, calculate:
(a) the current,
(b) the resistance of the heater,
(c) the energy consumed in 2 hours, and
(d) the cost if 1 kWh is priced at Rs 4.60.
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Solution
Given:
V=220V
`P=4KW=4xx10^3W`
(a) `I=P/V=(4xx10^3)/220=18.18A`
(b) `R=V/I=220/18.18=12.1 I `
(c)Energy consumed in two hours,`E=Pxxt`
`=4KWxx2h`
`=8Kwh`
(d) cost of 1kwh= Rs 4.6
Total cost =Energy consumed x price
= 8 x 4.6
= Rs 36.80
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