Question 1

What is one example of negative power?&#10;A) a battery charging&#10;B) current flowing through a resistor&#10;C) voltage across a capacitor&#10;D) impedance of an inductor

Accepted Answer

A

Question 2

Impedance is calculated by dividing ____ by ____.&#10;A) power; voltage&#10;B) voltage; power&#10;C) current; voltage&#10;D) voltage; current

Accepted Answer

Impedance is calculated by dividing voltage by current, as per Ohm's Law, which states that the voltage (V) across an element is equal to the product of the current (I) flowing through it and its impedance (Z), i.e., V = IZ.

Question 3

What is the unit of measurement for inductance?&#10;A) gilbert&#10;B) henry&#10;C) ohm&#10;D) farad

Accepted Answer

The unit of measurement for inductance is the henry (H).

Question 4

A noninductive coil has high ____ and no inductance.&#10;A) resistance&#10;B) reactance&#10;C) current&#10;D) frequency

Accepted Answer

A noninductive coil is designed to minimize inductance, which means it does not store energy in a magnetic field. However, it can still have high resistance, which opposes the flow of electric current through the material of the coil.

Question 5

The ____ value of an alternating current will produce the same heating effect as a specific value of a steady direct current.&#10;A) conversion&#10;B) instantaneous&#10;C) effective&#10;D) average

Accepted Answer

The effective value (also known as the root mean square or RMS value) of an alternating current is the value that would produce the same heating effect in a resistor as a direct current of the same value.

Question 6

In a purely capacitive circuit, the current will lead the voltage by ____ degrees.&#10;A) -90&#10;B) 90&#10;C) 180&#10;D) 360

Accepted Answer

In a purely capacitive circuit, the current leads the voltage by 90 degrees. This is a characteristic behavior of capacitors in AC circuits.

Question 7

Current ____ voltage in an inductor.&#10;A) lags&#10;B) leads&#10;C) is equal to&#10;D) is always in phase with

Accepted Answer

In an inductor, the current lags the voltage by 90 degrees due to the inductive reactance.

Question 8

In mutual induction, there is an electrical connection between two or more coils.

Accepted Answer

In mutual induction, two or more coils are magnetically linked but not electrically connected; the induction occurs through the magnetic field without direct electrical contact.

Question 9

The amount of voltage produced by a coil rotating in a magnetic field depends, in part, upon the strength of the magnetic field.

Accepted Answer

The voltage induced in a coil rotating in a magnetic field is directly proportional to the strength of the magnetic field, as described by Faraday's law of electromagnetic induction.

Question 10

Three-phase systems provide separate voltages that are ____ electrical time degrees apart.&#10;A) 90&#10;B) 120&#10;C) 180&#10;D) 360

Accepted Answer

In a three-phase system, the separate voltages are 120 electrical degrees apart, ensuring a constant power transfer over each cycle of the voltage waveform.

Question 11

Electromagnetic induction can be accomplished in two different ways: by moving a magnetic field across a coil, or a coil moving through the magnetic field.

Accepted Answer

The answer of Electromagnetic induction can be accomplished in two...

Question 12

The insulating material in a capacitor is called the ____.&#10;A) shield&#10;B) plate&#10;C) diaphragm&#10;D) dielectric

Accepted Answer

The answer of The insulating material in a capacitor is...

Question 13

In a DC circuit, a capacitor allows the current to flow only until the charge on the capacitor is ____.&#10;A) greater than the applied voltage&#10;B) equal to the applied voltage&#10;C) less than the applied voltage&#10;D) zero

Accepted Answer

The answer of In a DC circuit, a capacitor allows...

Question 14

The ease with which the voltage can be raised and lowered makes DC ideal for transmission purposes.

Accepted Answer

The answer of The ease with which the voltage can...

Question 15

Vector diagrams, drawn to scale, can be used to determine average power values.

Accepted Answer

The answer of Vector diagrams, drawn to scale, can be...

Deck 7: Alternating Current