LU 6 Alternating Current (6.1 & 6.2)

AC is more easily distributed than DC. This is because...

• AC can be transmitted using lighter wires

• AC can be transformed from a low voltage to a high voltage

• Wires have less resistance if they are carrying AC

• AC uses wires that totally insulated

Which of the following statements is TRUE about AC?

• AC can be obtained from the cell or battery

• AC voltages cannot be transformed to higher or lower voltage

• AC flows in one direction in the circuit

• AC allows the use of capacitor and inductor in the circuit

Which of the following statements is CORRECT about the rms value of an alternating voltage?

• It is twice the value of the peak voltage

• It is half the value of the peak voltage

• It is the same value of the equivalent DC voltage

• It is equal to square root 2 times the peak voltage

What is the peak voltage of the 230 V rms AC source?

• 115 V

• 325 V

• 163 V

• 230 V

The period of an AC wave, in seconds, is

• The same as the frequency in hertz

• Not related to the frequency in any way

• Equal to 1 divided by the frequency in hertz

• Equal to the peak amplitude divided by the frequency

In a perfect sine wave, the peak-to-peak amplitude is equal to

• Half the peak amplitude

• 1.414 times the peak amplitude

• The peak amplitude

• Twice the peak amplitude

Which of the following can vary with AC but never with DC?

• Power

• Frequency

• Resistor

• Amplitude

Suppose an AC signal has a frequency of 1770 Hz. What is its angular frequency?

• 1770 rad/s

• 11121 rad/s

• 282 rad/s

• Impossible to determine from the data given