Minimum output e.m.f. of the power source

[Janiceleong26]

Homework Statement

Homework Equations

V=IR
For resistors connected in parallel, 1/R =1/R1 + 1/R2 +...

The Attempt at a Solution

I first calculated the resistance of the the cable which consists of two wires,
1/R= 1/0.0050 + 1/0.0050
R = 2.5x10^-3 x 800
= 2 Ω
Then I calculate the voltage across the cable, V=0.060x2= 0.12V
So the total p.d would be 0.12V+16.0V=16.12V, and I chose A, but the correct answer is C. Why?
Please help, thanks

 

[jbriggs444]

Homework Equations

V=IR
For resistors connected in parallel, 1/R =1/R1 + 1/R2 +...

One of the wires in the cable carries current toward the relay and one carries the current back toward the power supply, right? If you drew that as a circuit diagram, would that makes those wires parallel or series?

 

[Janiceleong26]

One of the wires in the cable carries current toward the relay and one carries the current back toward the power supply, right? If you drew that as a circuit diagram, would that makes those wires parallel or series?

Oh right! It's series. I misread the question. I've figured out the answer already. Thank you!