A generator has a coil with 1260 turns that are each 0070 m

A generator has a coil with 1260 turns that are each 0.070 m in diameter. The coil rotates at 3600 rpm in a 0.670 T magnetic field. If a 80.0 resistive load is connected in parallel with the generator, what is the average power used by the load?

Solution

Area of coil

A=pi*D²/4 =pi*0.07²/4 =3.85*10^-3 m²

Induced Voltage

V_max=NBAW =1260*0.67*3.85*10^-3*(3600 *2pi/60)

V_max=1225 Volts

Rms Voltage

V_rms =1225/sqrt[2] =866.4 Volts

Average power

P_avg=V_rms²/R =866.4²/80

P_avg=9383 W or 9.38 KW