Coast Guard Exams
Question 546Electricity/Electronics - Assistant Engineer70% to pass

If a digital multimeter set up to measure AC volts reads slightly above 'zero' when its leads are disconnected, what is this a result of?

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.