ASVAB Electronics Information Test 2 — Questions and Answers
Question 1: What is the unit of electrical capacitance?
- Henry
- Farad (Correct answer)
- Ohm
- Siemens
Correct answer: Farad
Capacitance is measured in farads (F), named after Michael Faraday.
Question 2: In a parallel circuit with three 6-ohm resistors, what is the total resistance?
- 18 ohms
- 6 ohms
- 2 ohms (Correct answer)
- 3 ohms
Correct answer: 2 ohms
In parallel, total resistance = 1/(1/6+1/6+1/6) = 6/3 = 2 ohms.
Question 3: What does a diode primarily do in a circuit?
- Amplifies current
- Allows current to flow in only one direction (Correct answer)
- Stores electrical energy
- Measures voltage
Correct answer: Allows current to flow in only one direction
A diode is a semiconductor device that permits current to flow in one direction only.
Question 4: Which type of transformer steps voltage up from primary to secondary coil?
- Step-down transformer
- Isolation transformer
- Step-up transformer (Correct answer)
- Auto-transformer
Correct answer: Step-up transformer
A step-up transformer has more turns on the secondary coil than the primary, increasing voltage.
Question 5: What is the color code for a resistor with bands: Red, Red, Brown, Gold?
- 220 ohms ±5% (Correct answer)
- 2200 ohms ±5%
- 22 ohms ±5%
- 220 ohms ±10%
Correct answer: 220 ohms ±5%
Red=2, Red=2, Brown=×10 multiplier, Gold=±5% tolerance gives 220 ohms ±5%.
Question 6: What happens to capacitive reactance as frequency increases?
- It increases
- It remains constant
- It decreases (Correct answer)
- It doubles
Correct answer: It decreases
Capacitive reactance Xc = 1/(2πfC), so it decreases as frequency increases.
Question 7: Which semiconductor device can function as both a switch and an amplifier?
- Capacitor
- Resistor
- Transistor (Correct answer)
- Inductor
Correct answer: Transistor
A transistor can amplify signals or act as an electronic switch depending on how it is biased.
ASVAB Electronics Information Test 2
What is the unit of electrical capacitance?