ASVAB Electronics Fundamentals and Circuits 1 — Questions and Answers
Question 1: What is the unit of measurement for electrical current?
- Ampere (Correct answer)
- Volt
- Ohm
- Watt
Correct answer: Ampere
Electrical current is measured in amperes (amps). One ampere represents the flow of one coulomb of charge per second through a conductor.
Question 2: According to Ohm's Law, what is the relationship between voltage, current, and resistance?
- V = I × R (Correct answer)
- V = I ÷ R
- V = I + R
- V = I - R
Correct answer: V = I × R
Ohm's Law states that voltage (V) equals current (I) multiplied by resistance (R). This fundamental relationship is the basis for most electrical circuit analysis.
Question 3: What is the function of a resistor in a circuit?
- Limit the flow of current (Correct answer)
- Store electrical energy
- Generate voltage
- Convert AC to DC
Correct answer: Limit the flow of current
A resistor opposes the flow of electrical current, limiting how much current passes through a circuit. It converts electrical energy to heat energy in the process.
Question 4: In a series circuit with three resistors of 10Ω, 20Ω, and 30Ω, what is the total resistance?
- 60Ω (Correct answer)
- 5.45Ω
- 20Ω
- 30Ω
Correct answer: 60Ω
In a series circuit, total resistance is the sum of all individual resistances: R_total = 10 + 20 + 30 = 60Ω.
Question 5: What is the difference between AC and DC current?
- AC changes direction periodically; DC flows in one direction only (Correct answer)
- DC changes direction; AC flows in one direction
- AC is more powerful than DC
- There is no difference
Correct answer: AC changes direction periodically; DC flows in one direction only
AC (Alternating Current) periodically reverses direction, typically at 60 Hz in the US. DC (Direct Current) flows in one direction only. Batteries produce DC; power outlets provide AC.
Question 6: What is a semiconductor?
- A material with conductivity between a conductor and an insulator (Correct answer)
- A material that always conducts electricity
- A material that never conducts electricity
- A type of wire
Correct answer: A material with conductivity between a conductor and an insulator
A semiconductor is a material (like silicon or germanium) whose electrical conductivity falls between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (doping).
ASVAB Electronics Fundamentals and Circuits 1
What is the unit of measurement for electrical current?