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# A battery is supplying power to a tape-recorder by cable of resistance $0.02\Omega$. If the battery is generating $50W$ at $5V$, the power received by the tape-recorder is:

$\begin {array} {1 1} (A)\;50W & \quad (B)\;45W \\ (C)\;48W & \quad (D)\;30W \end {array}$

Can you answer this question?

$P = VI$
$\Rightarrow I = 10A$
Power loss in the cable $= I^2R = 100 \times 0.02 = 2W$
Hence, Power supplied to the tape-recorder is $48W$
Ans : (C)
answered Feb 10, 2014
edited Mar 14, 2014