Question

When a 20. 0-ohm resistor is connected across the terminals of a 12. 0-v battery, the terminal voltage of the battery falls 0. 30 v. what is the internal resistance of this battery

Answer 1

.513 Ω

Step-by-step explanation:

The current through the 20 Ω load can be found to be

(12-.3) v / 20 Ω = .585 A

This current also flows through the internal resistance and produces the .3 v drop across this resistor

V/I = R

.3 v / .585 A = .513 Ω internal resistance