ncreasing the frequency of rotation of the coils in an electrical generator increases the output emf. urn coil with a 0.250 m2 area is spun in the Earth's 5.00*10-5T field, producing a 12.0 kV maximum emf. At what angular velocity must the coil be spun?

The question is incomplete. The complete question is:

A 500-turn coil with a 0.250 m2 area is spun in the Earth's 5.00 * 10-5 T field, producing a 12.0 kV maximum emf. (a) At what angular velocity must the coil be spun? (b) What is unreasonable about this result? (c) Which assumption or premise is responsible?

Answer:

ω=1.92 * 106 rad/s

Explanation:

Emfo = 12.0*10^3 V

N = 500 turns

A = 0.250 m^2

B = 5.00*10^-5

ω=?

From

Emfo = NABω

ω = Emfo/NAB

ω = 12.0*10^3/500*0.250*5.00*10^-5

ω=1.92 * 106 rad/s

b) This angular velocity is unreasonably high, it is very much higher than a value that can be obtained for any mechanical system.

c) The unreasonable assumption or premise that a peak voltage as high as 12.0kV may be obtained.