An ac voltage vi =140 sin (100 t) V is applied to the primary coil having 200 turns, of an ideal 

An ac voltage vi = 140 sin (100 t) V is applied to the primary coil having 200 turns, of an ideal transformer and it supplies a power of 5 kW. If the secondary coil has 1000 turns, find :
(a) the output voltage,
(b) the instantaneous voltage across the secondary coil, and
(c) the current in the secondary coil. (Take 2 = 1·4)