Coast Guard Exams
Question 22Electricity/Electronics - Assistant Engineer70% to pass

If a digital multimeter is set up as shown in figures "A" and "B" of the illustration, what is the status of the silicon diode if the display reads 4.7 ohms when configured as in figure "A" and reads 490 ohms when configured as in figure "B"? Illustration EL-0211

Diagram for question 22
AI Explanation
The correct answer is B) the diode is functioning properly. The low resistance reading of 4.7 ohms in figure A indicates that the diode is conducting, which is the expected behavior for a properly functioning diode. The higher resistance reading of 490 ohms in figure B indicates that the diode is blocking current in the reverse direction, also a normal characteristic of a properly functioning diode. The other answer choices are incorrect because an open diode would read infinite resistance in both figures, a shorted diode would read near-zero resistance in both figures, and an intermittently open diode would exhibit inconsistent resistance readings.