A loop with 10 turns and radius of 0.4 m is placed perpendicularly in a uniform magnetic field. A 40 V electromotive force is induced in the loop. After 10 s the radius of the loop is decreased to 0.2 m. Calculate the
(a) initial area of the loop.
(b)new area of the loop when it is decreased.
(c) magnitude of the magnetic field.

answer: the correct answer id option(d).

explanation:

snell's law refraction:

the angle of refraction =

the angle of incidence =

refractive index of air = = 1

refractive index of glycerol = 1.47

from the given options, the most closest answer to 63.72° is 65° of option (d).

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

so easy. just google the electromagnetic waves and it’ll pop up.