Power P is to be delivered to a device via transmission cables having resistance . If V is the voltage across R and I the current through it, find the power wasted and how can it be reduced.
Hint: The power transmitted depends on the current in the wires.
Step 1: Find the power transmitted and the power consumption.
The power consumption in transmission lines is given by ,where is the resistance of transmission lines.
The power transmitted is given by:
P = VI
Step 2: Find the desirable conditions to transmit the power with low wastage.
The given power can be transmitted in two ways namely (i) at low voltage and high current or (ii) high voltage and low current.
In power transmission at low voltage and high current, more power is wasted as P=VI whereas power transmission at high voltage and low current facilitates the power transmission with minimal power wastage.
The power wastage can be reduced by transmitting power at high voltage.
