In: Physics
A 26-turn circular coil has a diameter of 0.60 m. It is placed with its axis along the direction of a 50.0-?T magnetic field and then flipped through an angle of 180° in 0.170 s. Determine the average emf generated in the coil, and the magnitude of the emf at 0.085 s. [4.3 x 10-3 V, 6.8 x 10-3 V] (Note: Very few students got the second part correct, you need to find the function for emf with respect to time and plug in time t.)
No.of truns N = 26
daimeter D = 0.6 m
radius R = 0.3 m
Earth's magnetic field B = 50 ?T
= 50 * 10 ^ -6 T
time interval dt = 0.17 s
Average induced emf E = N A [ B cos 0 - B cos 180] / dt
= 2NBA / dt
where A = area of the loop = ? R ^ 2
=0.2826 m ^ 2
Substitute value to get average emf at 0.17 s.
E = 4.32*10^-3 V.
After t = 0.085 s
So, E = 8.6*10^-3 V