Engineering Board Exam Reviewer · Energy and Power · hard
A 5 kW load is supplied through a line of total resistance 0.5, . How much power is lost in the line if the supply voltage is 230 V (assume the load voltage equals the supply voltage)?
- 2.36 W
- 236.3 W
- 5,000 W
- 2500 W
Answer
B. 236.3 W
Solution
I=P/V=5000/230=21.74 A. Line loss =I2R=(21.74)2(0.5)=236.3 W.
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