JEE Mains · Physics · STD 12 - 3. current electricity
An electric power line having total resistance of 2 Ω, delivers 1 kW of power of 250 V. The percentage efficiency of transmission line is: __________ .
- A 96.9
- B 86.5
- C 100
- D 92.5
Answer & Solution
Correct Answer
(A) 96.9
Step-by-step Solution
Detailed explanation
\( P_{out}=1000\,W \) \( P=VI \) \(1000=250 \times I\) I=4A \( P_{loss}=I^{2}R=(4)^{2}\times2=3200\, \) \( P_{net}=1000+32=103200\, \) \( \eta=(\frac{P_{out}}{P_{net}})\times100=\frac{1000}{1032}\times100=96.89\% \)
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