If the flux of DC motor approaches zero, its speed will
A. Remain unchanged.
B. Approach zero.
C. Aprroach infinity.
D. Between zero and infinity.
Show Answer
Answer: C
Share your understanding of this question with the correct explanation.
If the flux of a DC motor approaches zero, its speed will approach infinity.
The speed of a DC motor is given by the equation:
N = (V - E) / kφ
where N is the speed, V is the applied voltage, E is the back electromotive force (EMF) of the motor, k is a constant, and φ is the flux.
When the flux approaches zero, the denominator in the equation becomes very small, resulting in a large value for the speed N. As the flux decreases, the back EMF E also decreases, leading to an increase in the speed of the motor.
Therefore, as the flux of a DC motor approaches zero, its speed will approach infinity.
Hence, the correct answer is C: Approach infinity.