What is the main source of error in a null detector?(a) lower current detection ability(b) insufficient sensitivity of the null detector(c) wiring resistance(d) power dissipationI got this question during an interview.Question is from Measurement Errors in a Wheatstone Bridge in portion Measurement of Resistance of Electrical Measurements

What is the main source of error in a null detector?(a) lower current

1.	What is the main source of error in a null detector?(a) lower current detection ability(b) insufficient sensitivity of the null detector(c) wiring resistance(d) power dissipationI got this question during an interview.Question is from Measurement Errors in a Wheatstone Bridge in portion Measurement of Resistance of Electrical Measurements
Answer» CORRECT choice is (b) insufficient SENSITIVITY of the NULL DETECTOR To elaborate: Resistance of contact wires and POWER dissipation are some of the causes for error in a null detector. But insufficient sensitivity is the major source of error in a null detector such as a galvanometer.

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