Exam 15: Electromagnetism

The permeability of a material is similar in many respects to the conductivity in electric circuits.

The SI abbreviation for ampere-turn is A.

Energy wasted in heat as the molecular dipoles lag the magnetizing force is called the

When magnetic flux moves, the motion of magnetic lines cutting across a conductor forces free electrons in the conductor to move and produce current by an action called ______________.

The physical motion from the forces of magnetic fields is called ______________ action.

The symbol generally used for rate of change is

The practical unit for magnetomotive force is the

An effect of a force in producing rotation is called ______________.

Relay contacts may chatter if they are ______________.

To have electromagnetic induction, the conductor and the magnetic lines of flux must be

What is the ampere-turns of mmf for a coil with 2000 turns and a 10 mA current?

______________ law is the basic principle for determining the direction of an induced voltage or current.

Whose law or theorem is the basic principle for determining the direction of an induced voltage or current?

Hysteresis means lagging behind.

Energy wasted in heat as the molecular dipoles lag the magnetizing force is called the hysteresis loss.

The amp-clamp's probe senses the strength of the magnetic field set up by current in the wire and the meter deflection is proportional to the amount of current.

What device operates because a current is supplied so that an associated magnetic field can react with the external flux to produce motion of the conductor?

The cgs unit for field intensity is the

The mmf of a coil is

Hysteresis means