Answer:
0.000162V
Explanation:
r = Radius = 1.9 mm
r = 1.9÷1000
r = 0.0019m
emf = dΦ / dt
B_i = Initial magnetic field = 0
B_f = Final magnetic field = 1.5 T
t = Time taken = 105 ms
Induced emf is given by
emf = dΦ / dt
Emf= A ( Bf - Bi )/dt
emf = 3.142 × 0.0019 ×0.0019 × 1.5/ 0.105
end = 0.00001701 ÷ 0.105
emf = 0.0001620 V
Hence the induced elf is 0.0001620V
Answer: 1.61*10^-4 V
Explanation:
Given
Radius of the circular region, r = 1.9 mm = 0.0019 m
time, t = 105 ms
emf = dΦ / dt
ΔΦ = BA where,
ΔΦ is change in magnetic flux
ΔB is the change in the strength of magnetic field
A is the area of the circular region
Area, A = πr² = 3.142 * 0.0019 * 0.0019 = 1.13*10^-5 m²
emf = dΦ / dt
emf = BA / t
emf = (1.5 * 1.13*10^-5) / 105
emf = 1.695*10^-5 / 105*10^-3
emf = 1.61*10^-4 V
Therefore, the average induced emf is 1.61*10^-4 V
