A 60-turn coil has a diameter of 13 cm. The coil is placed in a spatially uniform magnetic field of magnitude 0.60 T so that the face of the coil and the magnetic field are perpendicular. Find the magnitude of the emf induced in the coil (in V) if the magnetic field is reduced to zero uniformly in the following times.

(a) 0.80 S 0.5973V

(b) 8.0 s 5.973 Xv

(c) 70 S 6.838 - 3 v

a) 0.5985 V

b) 0.05985 V

c) 0.00684 V

Explanation:

Given that

Number of turn in the coil, N = 60 turns

Magnetic field of the coil, B = 0.6 T

Diameter of the coil, d = 0.13 m

If area is given as, πd²/4, then

A = π * 0.13² * 1/4

A = 0.0133 m²

The induced emf, ε = - N (dΦ*m) / dt

Note, Φm = BA

Substituting for Φ, we have

ε = - NBA/t.

Now, we substitute for numbers in the equation

ε = - (60 * 0.6 * 0.0133) / 0.8

ε = 0.4788/0.8

ε = 0.5985 V

at 8s,

ε = - (60 * 0.6 * 0.0132) / 8

ε = 0.4788/8

ε = 0.05985 V

at 70s

ε = - (60 * 0.6 * 0.0132) / 70

ε = 0.4788/70

ε = 0.00684 V