# Electronics - Alternating Current vs Direct Current

### Exercise :: Alternating Current vs Direct Current - General Questions

21.

AC effective voltage is named:

 A. average B. peak C. peak-to-peak D. root mean square

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.

22.

If a voltmeter measures a sine wave as 500 mV, what would be its average value?

 A. 159.0 mV B. 318.5 mV C. 353.5 mV D. 451.0 mV

Answer: Option D

Explanation:

Some AC Voltage Conversion:

Peak to rms: multiply peak by 0.707.

Peak to average: multiply peak by 0.637.

Rms to peak: multiply rms by 1.414.

Rms to average: multiply rms by 0.9.

Average to rms: multiply avg by 1.111.

Average to peak: multiply avg by 1.567.

Mostly voltmeter shows rms value. So, Vav = 0.9*Vrms

= 0.9*500.

= 450mV ~ [D] 451 mV.

23.

One adjustable knob on the oscilloscope that allows the trace to be aligned with a reference graticule is called the:

 A. position control B. focus control C. intensity control D. volts/cm control

Answer: Option A

Explanation:

No answer description available for this question. Let us discuss.

24.

Signal comparisons may be most easily seen when using which item of test equipment?

 A. spectrum analyzer B. multimeter C. function generator D. dual trace oscilloscope

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.

25.

The magnitude that an alternation varies from zero is called its:

 A. altitude B. amplitude C. attitude D. polarity

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

#### Current Affairs 2021

Interview Questions and Answers