ASVAB Electronics Information Test 4 — Questions and Answers
Question 1: What is the relationship between inductive reactance and frequency?
- Inversely proportional
- Not related
- Directly proportional (Correct answer)
- Exponentially proportional
Correct answer: Directly proportional
Inductive reactance XL = 2πfL, so it increases proportionally as frequency increases.
Question 2: What is the function of a rectifier in a power supply?
- Converts DC to AC
- Filters noise from signals
- Converts AC to DC (Correct answer)
- Regulates output voltage
Correct answer: Converts AC to DC
A rectifier uses diodes to convert alternating current (AC) into direct current (DC).
Question 3: When two capacitors are connected in series, the total capacitance is:
- Greater than either capacitor
- Equal to the sum of both
- Less than the smallest capacitor (Correct answer)
- Equal to the largest capacitor
Correct answer: Less than the smallest capacitor
Series capacitors combine like parallel resistors: 1/Ct = 1/C1 + 1/C2, yielding a smaller total.
Question 4: What is the purpose of a voltage regulator IC in a circuit?
- Convert AC to DC
- Maintain a stable output voltage despite input variations (Correct answer)
- Amplify weak signals
- Filter high-frequency noise
Correct answer: Maintain a stable output voltage despite input variations
A voltage regulator IC keeps the output voltage constant regardless of load or input fluctuations.
Question 5: What type of logic gate outputs HIGH only when all inputs are HIGH?
- OR gate
- NAND gate
- NOR gate
- AND gate (Correct answer)
Correct answer: AND gate
An AND gate produces a HIGH output only when every input is HIGH; otherwise, output is LOW.
Question 6: A circuit draws 3 amperes from a 9-volt battery. What is the circuit's resistance?
- 27 ohms
- 6 ohms
- 3 ohms (Correct answer)
- 0.33 ohms
Correct answer: 3 ohms
Using Ohm's Law: R = V/I = 9/3 = 3 ohms.
Question 7: What is the purpose of a bypass capacitor placed near an IC power pin?
- Increase supply voltage
- Filter high-frequency noise on the power supply line (Correct answer)
- Store energy for backup power
- Block DC current from the IC
Correct answer: Filter high-frequency noise on the power supply line
A bypass (decoupling) capacitor filters high-frequency noise and voltage spikes from the power supply.
ASVAB Electronics Information Test 4
What is the relationship between inductive reactance and frequency?