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JEE Mains · Physics · STD 12 - 3. current electricity
An electrical power line, having a total resistance of \(2 \Omega\), delivers \(1 \,kW\) at \(220\, V\). The efficiency of the transmission line is approximately \(.......\%\)
- A \(72\)
- B \(96\)
- C \(91\)
- D \(85\)
Answer & Solution
Correct Answer
(B) \(96\)
Step-by-step Solution
Detailed explanation
\(vi =10^{3}\) \(i =\frac{1000}{220}\) loss \(= i ^{2} R =\left(\frac{50}{11}\right)^{2} \times 2\) efficiency \(=\frac{1000}{1000+ i ^{2} R } \times 100=96 \%\)
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