Question 1:

The resistances of a copper wire and an aluminium wire are equal. What is the ratio of the diameters dow/da if they have the same length? The resistivity of copper is 1.7 x 10 0 . m and the resistivity of aluminium is 2.8 x 10 0 . m.A transmission line 120 km long has a resistance of 18 ? and carries a current of 900 A. What is the potential difference between two pilons separated by 130 m?A |::Iatter;-..f delivers 31'] row to a small 9 resistor. How man}f electrons leave the batten...r in J; minutes? C] electrons