A more complex single-loop circuit contains two ideal batteries and three identical lightbulbs (each modeled as a 12Ω resistor). Starting at point P and moving clockwise around the loop, the components appear in the following order:
1. Battery 1 with its positive terminal oriented toward point P (emf ε1=9.0V).
2. Bulb A.
3. Bulb B.
4. Battery 2 with its positive terminal oriented opposite that of Battery 1 (emf ε2=6.0V).
5. Bulb C.
Assume connecting wires have negligible resistance.
(a) Determine the net electromotive force (emf) of the two batteries as sensed around the loop starting at point P and proceeding clockwise.
(b) Using the net emf you found in part (a), decide the direction of the conventional current in the loop. Indicate this direction with arrows on a clearly labeled schematic.
(c) Calculate the current that flows through each bulb once the circuit reaches steady state.
(d) Rank the bulbs in order of brightness and justify your ranking in terms of the potential difference across each bulb and the current you calculated.