Question 1

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

Accepted Answer

This statement is false. DC is not ideal for transmission purposes because it is more difficult and expensive to transmit over long distances than AC. AC can be easily transformed to higher or lower voltages using transformers, whereas DC requires more complex and expensive equipment. AC is therefore the preferred choice for long-distance transmission of electrical power.

Question 2

What is the unit used to measure inductance?&#10;A) gilbert&#10;B) henry&#10;C) ohm&#10;D) farad

Accepted Answer

The unit used to measure inductance is henry (H). Gilbert (Gb) is the unit of magnetomotive force, ohm (Ω) is the unit of resistance, and farad (F) is the unit of capacitance.

Question 3

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

In a DC circuit, a capacitor allows current to flow until it is fully charged, at which point the voltage across the capacitor is equal to the applied voltage.

Question 4

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

The answer of Current ____ voltage in an inductor.&#10;A) lags&#10;B)...

Question 5

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

Accepted Answer

Vector diagrams can be used to determine instantaneous power values, but average power values are typically calculated using integrals.

Question 6

Three-phase systems provide 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 three voltages or currents are 120 electrical degrees apart, as each phase is separated from the other two by 120 degrees.

Question 7

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

Accepted Answer

Charging a battery is an example of negative power because it involves storing energy, which is considered negative power in the context of power flow direction.

Question 8

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 9

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

Accepted Answer

According to Ohm's Law, impedance (Z) is equal to voltage (V) divided by current (I), therefore the answer is D) voltage, current.

Question 10

The ____ value of an alternating current is that value that 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 of an alternating current is also known as the root mean square (RMS) value, which represents the DC equivalent of an AC wave. It is the value of the current that produces the same heating effect as a specific value of a steady direct current. The other choices (conversion, instantaneous, and average) are not directly related to this concept.

Question 11

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

Accepted Answer

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

Question 12

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

Accepted Answer

The answer of The amount of voltage produced by a...

Question 13

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

Accepted Answer

The answer of A noninductive coil has high ____ and...

Question 14

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

Accepted Answer

The answer of In mutual induction, there is an electrical...

Question 15

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

Accepted Answer

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

Deck 7: Alternating Current