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Module 3. Electrical fundamentals

What is the power dissipated in a 500 ohm resistor with a 3A flow?

  • 1.5 kW.
  • 4.5 kW.
  • 750 kW.

Explanation

With current and resistance known, use P = I squared x R = 3 squared x 500 = 9 x 500 = 4500 W = 4.5 kW. The 1.5 kW answer comes from using P = I x R rather than the correct I squared term.

Sbrangy asking:

How?

Community Comments (2)

S
s.radovanovic Posts: 1 19.05.2022 / 14:01
P=I*E
E=I*R
R=500OHM
I=3A
P=4500W=4.5KW
W
Willy79 Posts: 2 04.12.2025 / 15:40
P = (I * I) * R

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