Power $P$ is to be delivered to a device via transmission cables having resistance $R_C$. If $V$ is the voltage across the device and $I$ is the current through it,find the power wasted and how can it be reduced.

(N/A) The power wasted in the transmission cables due to their resistance $R_C$ is given by the formula $P_{loss} = I^2 R_C$,where $I$ is the current flowing through the cables.
Since the total power delivered is $P = VI$,we can express the current as $I = P/V$.
Substituting this into the power loss formula,we get $P_{loss} = (P/V)^2 R_C = P^2 R_C / V^2$.
From this expression,it is clear that the power loss is inversely proportional to the square of the voltage $(P_{loss} \propto 1/V^2)$.
Therefore,to reduce the power wasted,the transmission should be done at a very high voltage $V$ and a correspondingly low current $I$.