Which of the following is NOT sufficient to measure the resistance of an unknown resistor?

Correct answer: D. Battery, ammeter, galvanometer, switch, connecting wires

  • A. Battery, voltmeter, ammeter, connecting wires, switch
  • B. Battery, galvanometer, 3 known resistors, switch, connecting wires
  • C. Battery, ohmmeter, connecting wires
  • D. Battery, ammeter, galvanometer, switch, connecting wires

Explanation

The correct answer is Option D. This setup does not have the necessary equipment to measure voltage or resistance directly, as it lacks both a voltmeter and an ohmmeter. An ammeter alone cannot provide the necessary data to calculate resistance without a corresponding voltage measurement.Options A and C are sufficient because they involve either a direct resistance measurement with an ohmmeter or the application of Ohm's Law using both current and voltage measurements. Option B is also sufficient as it effectively uses a Wheatstone bridge to determine the unknown resistance through balance, a known and reliable method.

Last updated

Related questions