PointstoStripes

Electronics Information (EI)

Electronics Information (EI) tests your grasp of electricity, circuits, and common components. It's not an AFQT subtest, but a strong score opens the door to electronics, communications, and technical jobs.

Practice questions

Original Electronics Information questions in the ASVAB style. Pick an answer for instant feedback and an explanation, then keep going in the app.

  1. A circuit has a voltage of 12 volts across a resistor with a resistance of 4 ohms. According to Ohm's law, how much current flows through the resistor?

    1. 3 amps
    2. 8 amps
    3. 16 amps
    4. 48 amps

    Ohm's law states I = V / R. Dividing 12 volts by 4 ohms gives 3 amps.

  2. Three resistors of 10 ohms, 20 ohms, and 30 ohms are connected in series. What is the total resistance of the circuit?

    1. 6 ohms
    2. 20 ohms
    3. 60 ohms
    4. 600 ohms

    In a series circuit, total resistance is the sum of the individual resistances. 10 + 20 + 30 equals 60 ohms.

  3. Which electronic component stores electrical energy in an electric field and is often used to smooth out voltage in a power supply?

    1. Resistor
    2. Capacitor
    3. Transistor
    4. Diode

    A capacitor stores energy in an electric field between its plates and is commonly used to filter or smooth voltage. A resistor limits current and a diode allows current in one direction.

  4. Which of the following materials is the best conductor of electricity?

    1. Rubber
    2. Glass
    3. Copper
    4. Dry wood

    Copper is a metal with many free electrons, making it an excellent conductor. Rubber, glass, and dry wood are insulators that resist current flow.

  5. An electronic component that allows current to flow in only one direction is called a:

    1. Resistor
    2. Diode
    3. Capacitor
    4. Inductor

    A diode conducts current in one direction (forward bias) and blocks it in the other (reverse bias). This makes it useful for converting AC to DC.

  6. A 24-volt source is connected to a resistor, and 2 amps of current flow through it. What is the resistance of the resistor?

    1. 12 ohms
    2. 22 ohms
    3. 26 ohms
    4. 48 ohms

    Rearranging Ohm's law gives R = V / I. Dividing 24 volts by 2 amps yields 12 ohms.

Get unlimited Electronics Information practice, instant explanations, and progress tracking in the Points to Stripes app.

Download on theApp StoreGet it onGoogle Play

What it measures

The Electronics Information (EI) subtest measures how well you understand basic electricity and electronics: how current flows, how circuits are built, and what common components do. Questions range from plain vocabulary ("what is measured in ohms?") to short calculations using Ohm's law.

EI is not one of the four AFQT subtests, so it does not directly affect your AFQT score or your basic eligibility to enlist. Instead, EI feeds several line-score composites that qualify you for specific jobs. A strong EI score is especially valuable for electronics, communications, avionics, radar, and other technical career fields. If you're aiming for one of those roles, this subtest matters a great deal even though it doesn't touch your AFQT number.

What's on it

  • Basic electrical terms and units: voltage (volts), current (amps), resistance (ohms), and power (watts)
  • Ohm's law and simple power calculations
  • Series and parallel circuits, and how each affects resistance and current
  • Conductors, insulators, and semiconductors, and which materials fall into each group
  • Common components: resistors, capacitors, inductors, transformers, diodes, transistors, and batteries
  • Circuit symbols and reading basic schematics
  • Alternating current (AC) versus direct current (DC), frequency, and grounding
  • Basic electrical safety and the effects of current

How to study it

Start by locking in the core relationships. Memorize the Ohm's law triangle (V = I x R) and the power formula (P = V x I), then practice rearranging them to solve for whichever value is missing. Most EI math is a single step once you plug in the right numbers, so speed comes from recognizing the formula instantly rather than from hard arithmetic. Also memorize the four basic units and what each measures, since a surprising number of questions are simply vocabulary.

Next, learn the difference between series and parallel circuits. In series, resistances add up and the current is the same everywhere. In parallel, the total resistance is always smaller than the smallest single resistor. Draw a few simple circuits and label the flow of current until the two arrangements feel automatic. Spend time on component symbols too, so a schematic doesn't slow you down.

This is a shorter subtest with a tight time limit, so pace yourself and don't get stuck. If a calculation isn't coming quickly, estimate, mark your best guess, and move on.

Common mistakes to avoid: mixing up the series and parallel rules (adding resistances when they're in parallel), confusing units (calling current "volts"), forgetting to rearrange Ohm's law before plugging in numbers, and mislabeling materials. Remember that metals like copper and silver are excellent conductors, while rubber, glass, and plastic are insulators, and materials like silicon are semiconductors.

Keep studying