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What formula is used to calculate electrical power (P) in a DC circuit?

P = I x E.

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  1. P = I x E ✔
  2. P = E / I
  3. P = I2 x E

Why: DC electrical power equals current multiplied by voltage. In this notation, P is power, I is current, and E is voltage.

Huh, didn't know that: The formula gives watts when current is in amperes and voltage is in volts.

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What is a power formula's favorite dessert? PIE: power equals current times voltage.
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References

Answer: P = I x E. DC electrical power equals current multiplied by voltage. In this notation, P is power, I is current, and E is voltage.

  1. NCVEC 2026-2030 Technician Question Pool, T5C08 ncvec.org/downloads/2026-2030%20Technician%20Pool%20and%20Syllabus%20Public%20Release%20Feb%2019%202026.pdf
    A. P = I x E
    Checked 2026-10-09.

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