When an alternating voltage of 220V is applied across a device X, a current of 0.5 A flows through the
circuit and is in phase with the applied voltage. When the same voltage is applied across another device
Y, the same current again flows through the circuit but it leads the applied voltage by `pi'/'2` radians.
(a) Name the devices `X and Y.`
(b) Calculate the current flowing in the circuit when same voltage is applied across the series
combination of `X and Y`.