A battery has an e.m.f. of 12 V and an internal resistance of 500 milliohms. What will be its terminal voltage, when supplying a load of 20 ohms?
A) 0.293 V
B) 11.7 V
C) 12V

Question

Quizplus · Accepted Answer

We can use the formula V = E - IR, where V is the terminal voltage, E is the EMF, I is the current flowing through the circuit, and R is the total resistance of the circuit. Since the load is 20 ohms, the total resistance of the circuit would be 500 milliohms + 20 ohms = 20.5 ohms.

We can solve for I using Ohm's law, which states that I = V/R. Plugging in the values, we get I = 12V/20.5 ohms = 0.585 A.

Now we can plug in all the values into the formula for V: 
V = E - IR 
V = 12V - 0.585 A x 500 milliohms 
V = 11.7V

Therefore, the terminal voltage of the battery when supplying a load of 20 ohms would be 11.7V.

A Battery Has an E