Three resistors are connected to a battery with an unknown emf and unknown internal
resistance r, as shown below.
Ignore the resistance of the connecting wires.
8.1 In the definition of the emf of a battery given below, (a) and (b) represent
missing words or phrases.
The emf of the battery is the maximum (a) … supplied by a battery per (b) ….
passing through it.
Write down (a) and (b) in your ANSWER BOOK and next to each the missing
word or phrase. (2)
With switch S CLOSED, the voltmeter reads 2,63 V.
8.2 Calculate the equivalent external resistance of the circuit. (4)
Switch S is now OPENED and the voltmeter reads 2,8 V.
8.3.1 The internal resistance of the battery (8)
8.3.2 The emf of the battery (2)