Question

Q1:

What is the effective resistance (in Ω) of a car's starter motor when 142 A flows through it as the car battery applies 10.7 V to the motor?

Q2:

The cord from an appliance is too short to reach the wall outlet in your room. You have two extension cords to choose from.

(a) Find the voltage drop in the first extension cord having a 0.0440 Ω resistance and through which 7.60 A is flowing.
V

(b) The second extension cord is cheaper and utilizes thinner wire. It has a resistance of 0.440 Ω and the current flowing through it is 7.60 A. By what amount does the voltage supplied to the appliance change when the first extension cord is replaced by the second?
V

Answer 1

we know v= IR 10.7 = 142 R. R = 0.0753 R = 7.534102 ohm