In DC potentiometer measurements, a second reading is often ___

In DC potentiometer measurements, a second reading is often taken after reversing the polarities of the DC supply and the unknown voltage and the average of the two reading is taken.

This is with a view of eliminate the effects of

A. Stray magnetic fields.
B. Ripples of the DC supply.
C. Errorneous standardisation.
D. Stray thermal emfs.

Show Answer

Answer: D

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