When connected to a 4ohm resistor a battery has a terminal v

When connected to a 4-ohm resistor, a battery has a terminal voltage of 10.8 V but produces 12 V on an open circuit. Determine the Thevenin equivalent circuit for the battery.

Solution

clearly it gives Thevenin equivalent Volatage is open circuit voltage given as V_th = 12 volts

and replace voltage source with short circuit the open circuit or Thevenin Resistance is R_TH = 4 OHMS