Ajit had a high tension tower erected on his farm land. He kept complaining to the authorities to remove it as it was occupying a large portion of his land. His uncle, who was a teacher, explained to him the need for erecting these towers for efficient transmission of power. As Ajit realised its significance, he stopped complaining.

Answer the following questions:

(a) Why is it necessary to transport power at high voltage?

(b) A low power factor implies large power loss. Explain.

(c) Write two values each displayed by Ajit and his uncle.

#### Solution

(a)If high voltage is used to transmit power, then the current through the wire will be less as I = P/V. Hence, the power loss = I_{2}R will also be less.

(b)The power is given as P = VI cosθ, where cos is the power factor. To supply a given power at a given voltage of transmission, if cos is small, then according to the above equation, current I has to be large. This leads to a large power loss caused by heat which is given as H = I^{2}R. Hence, a low power factor implies large power loss.

(c)Values displayed by Ajit: Understanding in nature and proactive

Values displayed by uncle: Patience and intelligence