Updated: Dec 9, 2025 | Source: 2022-2026 Question Pool | Topic: T5C
T5C10T5C

How much power is delivered by a voltage of 12 volts DC and a current of 2.5 amperes?

Deep Dive: T5C10

The correct answer is B: 30 watts. With a voltage of 12 volts DC and a current of 2.5 amperes, the power delivered is 30 watts. Using the power formula P = I × E: P = 2.5 A × 12 V = 30 watts. This is a straightforward application of the power formula. 12 volts is a common battery voltage, and 2.5 amperes is a moderate current draw. The calculation is simple: 2.5 × 12 = 30. This power level might represent a small transceiver or a receiver's power consumption.

Why Other Answers Are Wrong

Option A: Incorrect. 4.8 watts would be the result of dividing (12 / 2.5 = 4.8), not multiplying. Power is I × E, not E / I. Option C: Incorrect. 14.5 watts would be the result of adding (12 + 2.5 = 14.5), not the correct power calculation. Option D: Incorrect. 0.208 watts would be the result of dividing (2.5 / 12 = 0.208), not the correct power calculation.

Exam Tip

Power = Current × Voltage. Remember: P = I × E. 2.5 A × 12 V = 30 W. Simple multiplication.

Memory Aid

**2**.**5**A × **1**2V = **3**0W (think '2.5 × 12 = 30')

Real-World Example

A small receiver operating from a 12-volt battery draws 2.5 amperes. The power consumed is 2.5 × 12 = 30 watts. This tells you the receiver's power consumption, which helps you calculate how long the battery will last and size appropriate power supplies.

Source & Coverage

Question Pool: 2022-2026 Question Pool

Subelement: T5C

Reference: FCC Part 97.313

Key Concepts

Power calculation P = I × E DC power Electrical calculations

Verified Content

Question from the official FCC Technician Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the T5C topic.