Question 546Electricity & Electronics - Assistant Engineer
70% to passIf a digital multimeter set up to measure AC volts reads slightly above 'zero' when its leads are disconnected, what is this a result of?
Acapacitors inside the meter storing charges
B'ghost' voltages due to electromagnetic energy in the air
Cdefinite miscalibration of the meter
Da poor ground for the meter case
AI Explanation
The correct answer is B) 'ghost' voltages due to electromagnetic energy in the air. When a digital multimeter is set to measure AC volts and its leads are disconnected, it may still display a small non-zero reading. This is due to the meter's sensitivity to electromagnetic fields in the surrounding environment, which can induce small 'ghost' voltages in the meter's circuitry. This is a normal and expected behavior, and does not indicate a problem with the meter's calibration or grounding. The other options are incorrect as they do not accurately explain this phenomenon.
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