A 15.0-m length of wire consists of 9.0m of copper followed by 6.0m of aluminum, both of diameter 1.5mm . A voltage difference of 85mV is placed across the composite wire.
A.) What is the total resistance (sum) of the two wires?
B.) What is the current through the wire?
C.) What is the voltage across the copper part?
D.) What is the voltage across the aluminum part?