Question

A transmission line (TL) of length L and conductance per unit length G' is connected to an ideal constant voltage generator V. The end of the line is terminated in a pure resistive load RL. Assume that the losses in the conductors are negligible. The current l(z) in the TL is measured in the middle of the TL (this is at z-L/2). If the load is reduced to half its original value, the current in the middle of the line will Increase by a factor 2 Decrease by a factor 2 Remain constant None of the above options

Answer 1

Answer:

The Current will decrease by a factor of 2

Explanation:

Given the conditions, it should be noted that the current in the circuit is determined by the LOAD. In other words, the amount of current generator will be producing depends upon the load connected to it.

Now, as the question says, the load is reduced to half its original value, we can write:

$P1 = \sqrt{3} (V) (I1) Cos\alpha ----- (1)$

$P2 = \sqrt{3} (V) (I2) Cos\alpha$

Since, P2 = P1/2,

$P1/2 = \sqrt{3} (V) (I2) Cos\alpha ----- (2)$

Dividing equations (1) and (2), we get,

P1 / (P1/2) = I1/ I2

$I2 = I1 / 2$

Hence, it is proved that the current in the transmission line will decrease by a factor of 2 when load is reduced to half.