CSLB C-10 Electrical ContractorElectrical Theory and CalculationsEasy
An electrician is troubleshooting a circuit with a measured voltage of 24V and a current of 0.5A. What is the total resistance of this circuit?
- A48 ohms
- B12 ohms
- C0.02 ohms
- D24.5 ohms
Show answer & explanationAnswer & explanation
Correct answer: A. 48 ohms
Using Ohm's Law, Resistance (R) = Voltage (V) / Current (I). So, R = 24V / 0.5A = 48 ohms.
Why the other options are wrong
- B. This would be V * I, which is power, not resistance.
- C. This would be I / V, an incorrect application of Ohm's Law.
- D. This is likely a sum of voltage and current, not a division.
Ohm's Law (Resistance)
Ohm's Law states that resistance (R) in a circuit is equal to the voltage (V) divided by the current (I).
- R = V / I
- V = I × R
- I = V / R
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