When the motor is at its maximum speed, then back electromotive force (emf) will be
Correct answer: A. Maximum
- A. Maximum
- B. Zero
- C. Intermediate values
- D. None of the above
Explanation
When an electric motor is operating at its maximum speed, the back electromotive force (EMF), often referred to as back emf or counter emf, is at its maximum value. This is a consequence of the motor generating a self-induced voltage that opposes the applied voltage and the flow of current. At maximum speed, the motor's back emf counteracts the applied voltage most effectively.
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Magnetic flux density and magnetic flux describe the strength of a magnetic field and the field passing through a surface. A charged particle moving through a magnetic field experiences a force perpendicular to its velocity and may follow circular or helical motion, depending on the angle between velocity and field.
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