Unit 14 Magnetic Induction

A coil has an inductance of 3 H and a wire resistance of 15 Ohms. How long will it take for the current to reach its full value?

1.0 seconds

What three factors determine the amount of voltage induced into a conductor?

1.The turns of wire. 2.The strength of the magnetic field. 3.The speed of the cutting action.

During the period of time called the first time comstant of an exponential curve, the current will rise to about _% of its full value?

63.2

When using the Left Hand Generator Rule, the center finger points to the direction of?

Current

Losses in the core of iron core inductors include _ and _ losses.

Eddy currents, Hysteresis

When a conductor cuts magnetic lines of force, a voltage is induced into the conductor. This principle is called?

Electormagnetic induction

The _ describes the rate of certain occurrences.

Exponential curve

The direction of induced current can be determined by using the _ Left Hand Generator Rule?

Fleming

A way of determining the relationships of the motion of the conductor, the magnetic field direction, and the direction of the induced current is by using the?

Left Hand Generator Rule

An induced voltage opposes the motion that causes it according to _?

Lenz's Law

When a closed loop of wire cuts through magnetic flux lines, a currents is induced into the loop. The current in the loop sets up a magnetic field that is in opposition to the original magnetic flux.

Lenz's Law

One device used for spike suppression in either direct or alternating current circuits is?

Metal Oxide varistor

The magnectic quantity Weber (Wb) is equal to 100,000,000 lines fo flux. If a conductor cuts through on Weber per second, then a voltage of _ volts(s) is induced into the conductor.

One

Inductors always _ a change of current?

Opposes

If a conductor is moved upward, the polarity of unduced voltage is reversed and the current flows in the _ direction?

Oppsite

The time required for current in a inductor to reah its full Ohm's law value is?

R-L time constant

If a voltage is being induced into a conductor by electromagnetic induction, reversing the direction of motion of the conductor will?

Reverse the polarity of th induced voltage.

When using the Left Hand Generator Rule, the thumb points to the direction of?

Thrust

A(n) _ may occur when the current flow through an inductor stops and the current also decreases at an exponential rate?

Voltage Spike

If current is flowing in a circuit containing an inductor and the power switch is opened, the magnetic filed surrounding the inductor collapses and induces voltage into the inductor is the result of?

Voltage spike

The unit of inductance is the _?

henry(H)