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What is the resistance of a circuit that draws 4 amperes from a 12-volt source?

3 ohms.

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  1. 16 ohms
  2. 48 ohms
  3. 3 ohms ✔

Why: Use R = E divided by I. Twelve volts divided by 4 amperes equals 3 ohms.

Huh, didn't know that: That 3-ohm load would dissipate 48 watts.

The dad joke
Why did the 12-volt battery split up its 4 amps? To find 3 ohms of peace and quiet.
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References

Answer: 3 ohms. Use R = E divided by I. Twelve volts divided by 4 amperes equals 3 ohms.

  1. NCVEC 2026-2030 Technician Question Pool, T5D06 ncvec.org/downloads/2026-2030%20Technician%20Pool%20and%20Syllabus%20Public%20Release%20Feb%2019%202026.pdf
    A. 3 ohms
    Checked 2026-10-09.

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Ham RadioWhat is the resistance of a circuit for which the applied voltage is 12 volts and the current flow is 1.5 amperes?Ham RadioWhat is the current in a circuit with an applied voltage of 120 volts and a resistance of 80 ohms?Ham RadioWhat is the current through a 100-ohm resistor connected across 200 volts?

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