A body enters in MRI machine in 10 sec. If the
magnetic field is 1.5 T and circumference of MRI
machine is 0.9 m then find out emf induced in the
body.
(1) 0.96 V (2) 9.6 V (3) 9.6 mV (4) 96 mV
Answers
answer : option (3) 9.6 mV
explanation : magnitude of induced emf = rate of change of magnetic flux.
= B (∆A/∆t)
= B (πr²/t) ......(1)
given, circumference = 0.9
so, 2πr = 0.9
or, r = 0.9/2π
then, πr² = π(0.9/2π)² = 0.81/4π ....(2)
putting equation (2) in equation (1),
induced emf = B (0.81/4πt)
now, B = 1.5 T , t = 10s,
so, induced emf = 1.5 × {0.81/(4 × 3.14 × 10)}
= 0.0096 V
= 9.6 × 10^-3 V
= 9.6 mV
hence, option (3) is correct choice.
Answer:
option (3) i.e 9.6 mV
Explanation:
magnitude of induced emf
= B (∆A/∆t)
= B (πr²/t) ......(1)
given, circumference = 0.9
so, 2πr = 0.9
or, r = 0.9/2π
then, πr² = π(0.9/2π)² = 0.81/4π ....(2)
putting equation (2) in equation (1),
induced emf = B (0.81/4πt)
now, B = 1.5 T , t = 10s,
so, induced emf = 1.5 × {0.81/(4 × 3.14 × 10)}
= 0.0096 V
= 9.6 × 10^-3 V
= 9.6 mV
hence, option (3) is correct.