A power source used in the workshop has an EMF of 110V. When a load is applied the PD at the terminals drops to 95V when a current of 3A is drawn. Calculate the internal resistance of the power source?
The internaal resistance is like a series resistor inside the battery that's got the missing 15V across it. Its carrying the full 3A current due to being in series
What equation relates voltage, current and resistance?