Circuit resistance is usually measured...

Question 1 of 270705eccefa3bacbc34ba4d47f6f

Circuit resistance is usually measured off-line (de-energized) with an ohmmeter. In the absence of an ohmmeter, however, resistance may be INDIRECTLY measured on-line (energized) using what meter (or meters)?

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Question 1 of 27070

🔍 Key Concepts

• Ohm’s Law relationship between voltage, current, and resistance • Difference between direct measurement of resistance (ohmmeter, power OFF) and indirect calculation (power ON) • Which common meters are normally used on energized circuits: voltmeter, ammeter, frequency meter

💭 Think About

• If you cannot measure resistance directly with an ohmmeter, how could you still find it by using Ohm’s Law? • Which type of meter tells you how many amps are flowing, and which tells you how many volts are present? Could using BOTH give you enough information to calculate resistance? • Does a frequency meter give any information that appears in Ohm’s Law?

✅ Before You Answer

• Recall that Ohm’s Law is $R = \tfrac{V}{I}$ for a DC or purely resistive AC circuit. • Identify which meters can give you V (voltage) and which can give you I (current) in an energized circuit. • Confirm that a frequency meter does not measure voltage or current magnitude, only system frequency (Hz).