Answer:
a)
b)
Explanation:
1) Notation
Power on the refrigerator:
Voltage
, so then the radius would be
, representing the length of the two wires.
, that represent the resistivity for the aluminum founded on a book
power lost in the transmission.
2) Part a
We can find the total power adding all the individual values for power:
From the formula of electric power:
We can solve for the current like this:
Since we know and the voltage 110 V, we have:
The next step would be find the cross sectional are for the aluminum cables with the following formula:
Then with this area we can find the resistance for the material given by:
With this resistance then we can find the power dissipated with the following formula:
And if we want to find the percentage of power loss we can use this formula
3) Part b
Similar to part a we just need to change the value for V on this case to 110KV.
We can solve for the current like this:
Since we know and the voltage 110 KV=110000V, we have:
The cross sectional area is the same
The resistance for the material not changes.
With this resistance then we can find the power dissipated with the following formula: