In the potentiometer arrangement shown, the driving cell A has emf ε and internal resistance r. The emf of the cell B is ε$$2$$ and internal resistance $$2r$$. The potentiometer wire CD is $$100$$ cm long. If balance is obtained with length CJ $$=$$ l, then

Question

In the potentiometer arrangement shown, the driving cell  A has emf ε and internal resistance r. The emf of the cell B is ε$$2$$ and internal resistance $$2r$$. The potentiometer wire CD is $$100$$ cm long. If balance is obtained with length CJ $$=$$ l, then

Infinity Learn · Accepted Answer

As potential gradient k in the potentiometer wire will be less than $$($$ε$$/100)$$ (v/cm) because of presence of r, so for the battery of emf $$($$ε$$/2)$$ the balance point l will be greater than $$50$$ cm as shown.$$l=$$ ε$$/2k$$< ε$$/100$$  ⇒  l>$$50$$  cm

In the potentiometer arrangement shown, the driving cell A has emf $ε$ and internal resistance r. The emf of the cell B is $\frac{ε}{2}$ and internal resistance 2r. The potentiometer wire CD is 100 cm long. If balance is obtained with length CJ = l, then

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In the potentiometer arrangement shown, the driving cell A has emf ε and internal resistance r. The emf of the cell B is ε2 and internal resistance 2r. The potentiometer wire CD is 100 cm long. If balance is obtained with length CJ = l, then

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Ready to Test Your Skills?

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In the potentiometer arrangement shown, the driving cell A has emf $ε$ and internal resistance r. The emf of the cell B is $\frac{ε}{2}$ and internal resistance 2r. The potentiometer wire CD is 100 cm long. If balance is obtained with length CJ = l, then