or
Subelement A
Principles
Section 8
Conduction
What is the term used to identify an AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage?
• Cosine voltage.
• Power factor.
• Correct Answer
Root mean square (RMS).
• Average voltage.

What is the term used to identify an AC voltage that would cause the same heating in a resistor as a corresponding value of DC voltage?

Root mean square (RMS).

RMS describes the behavior of a wave, such as in AC current. Its value is though it would have been a DC current.

For more info on RMS, please see Wikipedia's article on Root mean square.

For RMS application in electricity, please see Electronics Notes article on AC Resistance and Impedance

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What happens to reactive power in a circuit that has both inductors and capacitors?
• It is dissipated as heat in the circuit.
• Correct Answer
It alternates between magnetic and electric fields and is not dissipated.
• It is dissipated as inductive and capacitive fields.
• It is dissipated as kinetic energy within the circuit.

What happens to reactive power in a circuit that has both inductors and capacitors?

It alternates between magnetic and electric fields and is not dissipated.

Both inductors and capacitors go through the cycles of charge and discharge, passing electrons to each other in the process. In theory, nothing is dissipated.

In reality, there is wire resistance, etc, causing some loss.

For a lot more info, please see Electronic Tutorials site for the article on Reactive Power, and article on Power in AC Circuits

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Halving the cross-sectional area of a conductor will:
• Not affect the resistance.
• Quarter the resistance.
• Correct Answer
Double the resistance.
• Halve the resistance.

Halving the cross-sectional area of a conductor will:

Double the resistance.

The relationship between the cross-sectional area of a conductor and resistance is inversely proportional. If you cut in half one, you double the other.

For more info, please see presentation slide #5 on USNA site, for EE301 Lesson 2: Resistance (Chapter 3) and Ohms Law (Chapter 4)

Also, please view YouTube videos:
Factors On Which The Resistance Of A Conductor Depends

Factors affecting the resistance of a conductor - Kisembo Academy

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Which of the following groups is correct for listing common materials in order of descending conductivity?
• Correct Answer
Silver, copper, aluminum, iron, and lead.
• Lead, iron, silver, aluminum, and copper.
• Iron, silver, aluminum, copper, and silver.
• Silver, aluminum, iron, lead, and copper.

Which of the following groups is correct for listing common materials in order of descending conductivity?

Silver, copper, aluminum, iron, and lead.

For the table of conductivity, please see Thought Co site for the article on
Electrical Conductivity of Metals

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How do you compute true power (power dissipated in the circuit) in a circuit where AC voltage and current are out of phase?
• Multiply RMS voltage times RMS current.
• Subtract apparent power from the power factor.
• Divide apparent power by the power factor.
• Correct Answer
Multiply apparent power times the power factor.

How do you compute true power (power dissipated in the circuit) in a circuit where AC voltage and current are out of phase?

Multiply apparent power times the power factor.

For more info, please see Fluke Co., site for article on What is power factor and why is it important?

Also, from All About Circuits site, article True, Reactive, and Apparent Power.

See YouTube video from Engineering Mindset channel, called Power Factor Explained - The basics what is power factor pf

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Assuming a power source to have a fixed value of internal resistance, maximum power will be transferred to the load when:
• The load impedance is greater than the source impedance.
• Correct Answer
The load impedance equals the internal impedance of the source.
• The load impedance is less than the source impedance.
• The fixed values of internal impedance are not relative to the power source.

Assuming a power source to have a fixed value of internal resistance, maximum power will be transferred to the load when:

The load impedance equals the internal impedance of the source.

For explanation, please see Electronics Tutorials site for article on Maximum Power Transfer

Also, see YouTube video from The Organic Chemistry Tutor called Maximum Power Transfer Theorem Using Nodal Analysis & Thevenin Equivalent Circuits

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