The battery in the circuit diagram below has an emf of 12 V and an internal resistance
of 0,5 Ω. Resistor R has an unknown resistance.

8.1 What is the meaning of the following statement?
The emf of the battery is 12 V. (2)
The reading on the ammeter is 2 A when switch S is OPEN.
8.2 Calculate the:
8.2.1 Reading on the voltmeter (3)
8.2.2 Resistance of resistor R (2)
Switch S is now CLOSED.
8.3 How does this change affect the reading on the voltmeter? Choose from:
INCREASES, DECREASES or REMAINS THE SAME.
Explain the answer. (4)
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