Answer:
The current in wire resistance 2Ω
a). 8696 A
b). fraction power 15.1% a 115kV
Explanation:
Resistance
Ω/Km*40km
R=2Ω
P=1000 MW
a).

Using law ohm
b).


%
Answer:
Current, I = 1000 A
Explanation:
It is given that,
Length of the copper wire, l = 7300 m
Resistance of copper line, R = 10 ohms
Magnetic field, B = 0.1 T

Resistivity, 
We need to find the current flowing the copper wire. Firstly, we need to find the radius of he power line using physical dimensions as :




r = 0.00199 m
or

The magnetic field on a current carrying wire is given by :



I = 1000 A
So, the current of 1000 A is flowing through the copper wire. Hence, this is the required solution.
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