Question 1

If an aircraft full- Wave, dc power supply operates from a 400 Hz sineW ave, the ripple frequency is ________.
A)60 Hz
B)800 Hz
C)120 Hz
D)400 Hz

Accepted Answer

The ripple frequency of a full-wave rectified signal is twice the input frequency. Since the input frequency is 400 Hz, the ripple frequency is 2 * 400 Hz = 800 Hz.

Question 2

To generate light, an LED requires:
A)zener breakdown.
B)forward DC bias.
C)reverse DC bias.
D)avalanche breakdown.

Accepted Answer

LEDs operate by forward biasing a p-n junction, causing the release of light energy through the recombination of electrons and holes. Zener breakdown and avalanche breakdown are types of breakdown that occur in diodes when they are subjected to high reverse voltage, whereas reverse biasing a LED would result in minimal light emission.

Question 3

To operate as a voltage regulator, a zener diode requires a:
A)series capacitor.
B)transformer.
C)silicon diode.
D)series resistor.

Accepted Answer

A series resistor is required to limit the current through the zener diode and maintain a constant output voltage.

Question 4

In the simplest sense, a zener diode is really a:
A)voltage regulator.
B)reference current.
C)current regulator.
D)reference Voltage.

Accepted Answer

A Zener diode is primarily used as a voltage regulator by providing a stable reference voltage. It operates in the reverse breakdown region, maintaining a constant voltage across it for a wide range of current values.

Question 5

To detect light, a photodiode requires:
A)reverse bias.
B)avalanche breakdown.
C)forward bias.
D)zener breakdown.

Accepted Answer

Photodiodes are designed to operate in reverse bias, where they are most sensitive to light. In this mode, the electric field across the junction increases, allowing the photodiode to efficiently convert light into an electrical current.

Question 6

The formula for load regulation is: 
A)$\left[ \frac { \mathrm { V } _ { \mathrm { NL } } - \mathrm { V } _ { \mathrm { FL } } } { \mathrm { V } _ { \mathrm { FL } } } \right] \times 100 \%$ 
B)$\left[ \frac { \mathrm { V } _ { \mathrm { FL } } - \mathrm { V } \mathrm { NL } } { \mathrm { V } _ { \mathrm { FL } } } \right] \times 100 \%$ 
C)$\left[ \frac { \mathrm { V } _ { \mathrm { NL } } - \mathrm { V } _ { \mathrm { FL } } } { \mathrm { V } _ { \mathrm { NL } } } \right] \times 100 \%$ 
D)$\left[ \frac { \mathrm { V } _ { \mathrm { FL } } - \mathrm { V } _ { \mathrm { NL } } } { \mathrm { V } _ { \mathrm { NL } } } \right] \times 100 \%$

Accepted Answer

Load regulation is calculated as the percentage change in output voltage from no-load to full-load conditions, using the formula $\left[ \frac { \mathrm { V } _ { \mathrm { NL } } - \mathrm { V } _ { \mathrm { FL } } } { \mathrm { V } _ { \mathrm { FL } } } \right] \times 100 \%$.

Question 7

The formula for line regulation is: 
A)$\frac { \Delta \mathrm { V } _ { \mathrm { FL } } } { \Delta \mathrm { V } _ { \mathrm { NL } } } \times 100 \%$ 
B)$\frac { \Delta \mathrm { V } _ { \mathrm { IN } } } { \Delta \mathrm { V } _ { \mathrm { OUT } } } \times 100 \%$ 
C)$\frac { \Delta \mathrm { V } _ { \mathrm { NL } } } { \Delta \mathrm { V } _ { \mathrm { FL } } } \times 100 \%$ 
D)$\frac { \Delta \mathrm { V } _ { \mathrm { OUT } } } { \Delta \mathrm { V } _ { \mathrm { IN } } } \times 100 \%$

Accepted Answer

Line regulation refers to the ability of a power supply to maintain a constant output voltage regardless of changes in input voltage. Therefore, the formula for line regulation should relate the output voltage (Vout) to the input voltage (Vin). Option D expresses this relationship, where ΔVout is the change in output voltage and ΔVin is the change in input voltage. The percentage is multiplied by 100 to express the result as a percentage. Options A, B, and C express different relationships that are not relevant to line regulation.

Quiz 16: Regulators, Filters, and Op-Amps

If an aircraft full- Wave, dc power supply operates from a 400 Hz sineW ave, the ripple frequency is ________.

To generate light, an LED requires:

To operate as a voltage regulator, a zener diode requires a:

In the simplest sense, a zener diode is really a:

To detect light, a photodiode requires:

The formula for load regulation is:

The formula for line regulation is: