Question 525Electricity & Electronics - QMED
70% to passA switchboard ammeter indicates a reading slightly above 'zero' when the leads are disconnected. What is this caused by?
Acapacitors inside the meter storing charges
Ba poor ground for the meter case
Cstatic electricity in the air
Dmechanical misalignment of the meter pointer
AI Explanation
The correct answer is D) mechanical misalignment of the meter pointer. When the leads of a switchboard ammeter are disconnected, the meter should ideally read exactly zero. If the meter shows a reading slightly above zero, this is likely due to a mechanical misalignment of the meter pointer. This misalignment can occur over time due to wear and tear on the meter's internal components. The other options are incorrect - capacitors do not store a measurable charge when the leads are disconnected, a poor ground would not cause a reading, and static electricity would not affect the analog meter reading.
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