(A) Half
(B) increased
(C) same
(D) decreased
Answer: (D) decreased
Explanation:
Consider the transmission of electric power by a three-phase line
Let,
P = power transmitted in watts
V = line voltage in volts
cos φ = power factor of the load
Where,
L = length of the line in meters
R = resistance per conductor in ohms
ρ = resistivity of conductor material
a = area of X-section of conductor
The load current is given as,
From the above equation, we can say that if voltage increased then line loss will decrease and vice versa.
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