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Question
In a potentiometer experiment, balancing length is found to be 120 cm for a cell E1 of emf 2V. What will be the balancing length for another cell E2 of emf 1.5V? (No other changes are made in the experiment.)
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Solution
``E_1/E_2 = l_1/l_2`
`2/1.5 = 120/l_2`
`l_2 = 90 cm`
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