Two incandescent bulbs are marked as A: 60 W, 120 V and B: 60 W, 240 V.
(i) Calculate the resistance of each bulb when glowing at the rated voltage.
(ii) Both bulbs are now connected separately across a 240 V mains supply. Determine the current drawn by each bulb under this condition.
(iii) When operated at their respective rated voltages for 2 h, which bulb converts a greater amount of electrical energy into light and heat? Support your answer with suitable numerical comparison.
(iv) Explain, with calculation, which bulb will glow brighter when each is connected to the 240 V mains and why.