Question 77Electricity & Electronics - Assistant Engineer

The correct answer is B) 'zero'. When measuring the insulation resistance of a grounded switch or cable using a megohmmeter, the reading will indicate a 'zero' or very low resistance value. This is because a grounded circuit has a direct connection to the ground, effectively shorting out the insulation and causing the megohmmeter to read a near-zero resistance. The other options are incorrect because: A) being unsteady in the low range is not a definitive indication of a grounded circuit, C) being unsteady in the high range is more indicative of a high-resistance or open circuit, and D) infinity would indicate a completely open or disconnected circuit, which is the opposite of a grounded condition.