Question

A flat coil having 40 turns, each one of cross-sectional area 12.0 cm^2, is oriented with its plane perpendicular to a uniform magnetic field. The field varies steadily from 0.00 T to 1.20 T in 20.0 ms. What emf is induced in the coil during this time?

Answer 1

Answer:

The induced emf in the coil is 2.88 V

Explanation:

Given;

number of turns of the coil, N = 40

cross sectional area of the coil, A = 12.0 cm² = 12 x 10 ⁻⁴ m²

the magnetic field strength, B = 1.2 T

change in time, dt = 20 ms = 20 x 10⁻³ s

The emf induced in the coil is calculated as;

$emf = -N\frac{d\phi }{dt} \\\\emf = N (\frac{BA}{dt} )\\\\emf = \frac{40 \ \times \ 1.2 \ \times \ 12\times 10^{-4}}{20 \times 10^{-3}} \\\\emf = 2.88 \ V$  

Therefore, the induced emf in the coil is 2.88 V