AC Electricity

Question 1

How are Sine waves measured?

Answer 1

Sine waves are measured in frequency. Frequency is determined by the number of cycles that occur in one second.

Question 2

1/2 cycle on a AC Sine Wave is called what?

Answer 2

ALTERNATION

Question 3

The AC voltage of the circuit can be shown on the graph called what?

Answer 3

AC sine wave

Question 4

This sine wave has a frequency of ___ cycles per second, or ___ cps.

Answer 4

This sine wave has a frequency of 3 cycles per second, or 3 cps.

Question 5

Frequency is usually measured in what?

Answer 5

Frequency is usually measured in Hertz. 3 cps is equal to 3 Hertz (Hz).

Question 6

What three characteristics are needed for sine wave calculations?

Answer 6

• Frequency
  
  • Period
  • Wavelength

Question 7

The frequency of a sine wave is calculated how?

Answer 7

the frequency of a sine wave is calculated by the number of cycles per second.

Question 8

How is a period determined?

Answer 8

Period is determined by the time taken to complete one cycle of the sine wave.

Question 9

What is the symbol for period?

What is the symbol for frequency?

What is the formula for calculating period?

Answer 9

The symbol for period is T. The symbol for frequency is f. The formula for calculating period is:

T = 1/f

example: If frequency is is 3 Hz,

T = 1/f

T = 1/3

T = 0.33 seconds

Question 10

What is a wavelength?

What is the symbol for wavelength?

Answer 10

Wavelength is determined by measuring the actual distance between beginning and end of one cycle.

The symbol for wavelength is the Greek letter λ (lambda).

Question 11

Wavelength is expressed in ____ or ____.

Answer 11

Wavelength is expressed in meters or centimeters.

Question 12

What formula is used to calculate wavelength distance in meters?

Answer 12

Question 13

What is Induction?

Answer 13

Induction is the generation of AC current by changing a magnetic field (flux variation).

Question 14

In order to induce current, wat three things are required?

Answer 14

a conductor
a magnetic field
relative motion

Question 15

What is the left-hand rule to determine the direction of the magnetic field around the conductor?

Answer 15

Question 16

AC power is generated by moving a conductor through a _______.

Answer 16

AC power is generated by moving a conductor through a magnetic field.

Question 17

What is the peak value of a sine wave?

Answer 17

Peak is determined by the highest positive or negative voltage obtained.

Question 18

What is the peak-to-peak value of a sine wave?

Answer 18

The peak-to-peak value of this sine wave is determined by doubling the peak value.

Question 19

What is the average and RMS of a sine wave?

Answer 19

Average value is calculated using the sum of all angles contained in 180°. The constant 0.637 is used. Average is determined by multiplying 0.637 × the peak value of the sine wave. In this example 0.637 × 10 = 6.37 volts.

ROOT-MEAN-SQUARE (RMS) - The most common calculation is Root-Mean-Square. This is a comparison between the power generated in an AC signal with that of an equivalent DC voltage. RMS equals 0.707 × the peak value.

Question 20

What is the main difference between DC and AC electricity?

Answer 20

The difference between DC and AC is that voltage varies in an AC circuit, as indicated by the sine wave