EG1 CH.6

Question 1

Explain the conservation of energy.

Answer 1

Energy can neither be created nor destroyed, it can only be converted (changed from one form to another)

Question 2

Explain the law of charges.

Answer 2

Like charges repel, opposite charges attract

Question 3

T or F: If a conductor is passed near a magnet, current will flow if a complete circuit exists.

Answer 3

True

Question 4

T or F: The machine that converts mechanical motion into electrical energy does so by spinning a magnet inside a coil of wire.

Answer 4

True

Question 5

What is polarity?

Answer 5

When the voltage causes the electrons to move away (positive) or towards (negative) the generating source.

Question 6

What are the three factors that affect voltage strength?

Answer 6

Number of turns in the coil of wire, Strength of magnetic field, and speed at which the magnetic lines of flux pass through the coil.

Question 7

What does it take for a generator to produce one volt of electricity?

Answer 7

A single conductor must pass through 100,000,000 lines of flux in one second.

Question 8

T or F: If you increase the coils of a conductor, you will achieve a higher voltage without changing the speed or strength of the magnetic field.

Answer 8

True

Question 9

What is a sine wave in regards to voltage?

Answer 9

The graphical representation of an AC circuit.

Question 10

Explain what happens as a generator goes through one turn, in regards to Alternating Current.

Answer 10

At 1/4 turn, generator reaches max positive value. At 1/2 turn, generator reaches zero and no voltage is produced. At 3/4 turn, generator reaches max negative value. At 1 full turn, generator goes back to zero charge.

Question 11

T or F: Voltage only exists on the line when there is a positive charge.

Answer 11

False, a voltage exists whenever there is either a positive or negative charge.

Question 12

What is another name for a complete rotation of a generator?

Answer 12

cycle

Question 13

What is frequency, in regards to wavelengths?

Answer 13

The number of cycles in one second that a generator produces.

Question 14

What is frequency measured in?

Answer 14

Hertz (Hz)

Question 15

What is the frequency of power in the US and Canada?

Answer 15

60 Hz

Question 16

What is the equation to find the voltage along a sine wave?

Answer 16

E(inst)=E(max)*Sine(angle)

Question 17

How often does voltage fall to zero in a cycle?

Answer 17

3

Question 18

How is DC different than AC?

Answer 18

DC voltage is constant in its strength and polarity over time and has a continuous value.

Question 19

What do we use to compare DC to AC voltage?

Answer 19

RMS or Effective Value

Question 20

What does RMS stand for?

Answer 20

Root Mean Square

Question 21

What is the formula to find RMS?

Answer 21

RMS=0.707*Peak(V)

Question 22

What is the formula to find peak voltage?

Answer 22

Peak=1.414*RMS

Question 23

What is the only type of load found on a DC circuit?

Answer 23

Resistive

Question 24

What are the three types of load found on an AC circuit?

Answer 24

Resistive, Inductive, and Capacitive

Question 25

What does the type of load tell us?

Answer 25

It tells us the relationship between voltage and current.

Question 26

Explain phase angle relationship.

Answer 26

If voltage and current rise and fall together at the same time they are in phase. If voltage and current rise and fall at different times they are out of phase.

Question 27

Under what load does AC circuits produce true power?

Answer 27

Resistive