Capacitor code reading: Many small capacitors use a three-digit marking. For a device labeled 102, what is its capacitance value expressed in pF?
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A1000 pF
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B10,000 pF
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C1000 µF
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D10,000 µF
Answer
Correct Answer: 1000 pF
Explanation
Introduction:Component codes compress values onto tiny packages. Understanding the capacitor three-digit code is essential for quick identification during prototyping and repair.
Given Data / Assumptions:
- Code format: XY Z, where XY are significant digits and Z is the multiplier in pF.
- Marking is 102.
- Units are interpreted in picofarads unless otherwise stated.
Concept / Approach:Use the rule: capacitance (pF) = (first two digits) * 10^(third digit). Then, convert to nF or µF only if asked. Here we keep pF directly.
Step-by-Step Solution:1) Significant digits: 10.2) Multiplier: 10^2 = 100.3) Capacitance: 10 * 100 = 1000 pF.4) Optional conversions: 1000 pF = 1 nF = 0.001 µF.
Verification / Alternative check:Cross-check with standard EIA code tables for ceramic capacitors: 102 always maps to 1000 pF.
Why Other Options Are Wrong:10,000 pF: corresponds to 103, not 102.1000 µF and 10,000 µF: unrealistic for small coded ceramics; these are electrolytic-scale values.
Common Pitfalls:Misreading the third digit as a literal digit rather than a power-of-ten multiplier; forgetting default units are pF for this code system.
Final Answer:1000 pF