(2014?Huaihua a model) as shown in the figure for a small electric fan circuit sketch, where the ideal transformer turns ratio of the original and secondary coils for n, the original coil connected to

(2014?Huaihua a model) as shown in the figure for a small electric fan circuit sketch, where the ideal transformer turns ratio of the original and secondary coils for n, the original coil connected to the A, the fan motor is not pure resistance, so its voltage can not be Ir, should be equal to the voltage of the bulb, so A error;

B, the ideal transformer turns ratio of the original and secondary coils of the n, the original coil connected to the voltage of the U AC power supply, then the output voltage is

U

n

, and the input power of the motor is

UI

n

, the power of the bulb is I2R=

U2

n2R

, the input power is equal to the output power of

UI

n

+

U2

n2R

. Therefore, B is wrong;

C. The input power of the motor is

UI

n

, and the power consumed by the coil resistance of the motor is I2r, then the mechanical power of the motor D is

UI

n

-I2r. Therefore, C is correct;

D, because the voltage at the ends of the secondary coil is

U

n

, if the fan is stuck due to mechanical failure, the secondary coil circuit can be considered as a purely resistive circuit, and the equivalent resistance of this circuit is

R+r

Rr

, so the current in the secondary coil is

URr

n(R+r)

, and the current through the primary coil is , the current through the primary coil is

U(R+r)

n2Rr

, D is correct;

So, the choice is:CD