(a(i))[2]
The ammeter $A_1$ reads $0.25\,\text{A}$. The voltmeter $V_1$ reads $3.0\,\text{V}$. Determine the readings shown by the remaining meters.
(a(ii))[2]
Calculate the resistance value of resistor R.
(a(iii))[2]
The resistor satisfies Ohm’s law. State Ohm’s law.
(b)[3]
Fig. 6.2 gives the current-voltage graph for the filament lamp. In Fig. 6.1, the battery is replaced by a different battery with another e.m.f. The potential difference across the lamp increases to $6.0\,\text{V}$. Use information from the graph to work out the e.m.f. of the second battery. Show your working.