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$85$
JEE MAIN 2020, Medium
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B$96$
b $vi =10^{3}$
$i =\frac{1000}{220}$
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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