Difficulty: Easy
Correct Answer: 24 kΩ
Explanation:
Introduction / Context:Direct application of Ohm’s law V = I * R allows quick back-calculation of a resistor value from measured voltage and current. Careful attention to micro- units prevents decimal mistakes that are common in troubleshooting and exams.
Given Data / Assumptions:
Concept / Approach:Rearrange Ohm’s law to R = V / I. Convert microamperes to amperes before dividing to avoid a 10^6 error. Finally, express the answer in a convenient SI multiple (kΩ) for readability.
Step-by-Step Solution:
Convert current: 500 µA = 0.0005 A.Compute resistance: R = V / I = 12 / 0.0005 = 24,000 Ω.Express in kΩ: 24,000 Ω = 24 kΩ.Select the option that matches 24 kΩ.Verification / Alternative check:Cross-check using I = V / R with R = 24 kΩ: I = 12 / 24,000 = 0.0005 A = 500 µA, confirming consistency.
Why Other Options Are Wrong:
Common Pitfalls:Forgetting that 1 µA = 10^−6 A; mixing up milli and micro; failing to convert before dividing.
Final Answer:24 kΩ
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