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प्रश्न
When the balance point is obtained in the potentiometer, a current is drawn from ______.
विकल्प
Both the cells and auxiliary battery
Cell only
Auxiliary battery only
Neither cell nor auxiliary battery
उत्तर
When the balance point is obtained in the potentiometer, a current is drawn from auxiliary battery only.
Explanation:
When a null point is obtained in the potentiometer, a current depends only on the EMF of auxiliary battery and its resistance and resistance of cells.
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