A coil of circular cross-section having 1000 turns and 4 ~cm ^2 face area is placed with its axis parallel to a magnetic field which decreases by 10⁻² ~Wb m ⁻² in 0.01 ~s . The e.m.f. induced in the coil is:

Step-by-step solution

Given: No. of turns N=1000 Face area, A=4 ~cm ^2=4 10⁻⁴ ~m ^2 Change in magnetic field, B =10⁻² wbm ⁻² Time taken, t=0.01 ~s =10⁻² sec Emf induced in the coil e= ? Applying formula, Induced emf, e= -d d t aligned &=N ( B t ) A &= 1000 10⁻² 4 10⁻⁴ 10⁻² =400 mV aligned