A power transmission line feeds input power at 2200 V to a step-down transformer with its primary windings having 2000 turns. The output power is delivered at 220 V by the transformer. If the current in the primary of the transformer is 2 A and its efficiency is 80 % , the output current would be:

Step-by-step solution

The input power P_ in is given by the product of primary voltage V_p and primary current I_p . P_ in = V_p I_p = 2200 V 2 A = 4400 W The efficiency of the transformer is defined as the ratio of output power P_ out to input power P_ in . = P_ out P_ in P_ out = P_ in Given = 80 % = 0.8 , we calculate the output power: P_ out = 0.8 4400 W = 3520 W The output power is also given by the product of secondary voltage V_s and secondary current I_s . P_ out = V_s I_s 3520 W = 220 V I_s I_s = 3520 220 A = 16 A Answer: 16 A