JEE Mains · Physics · STD 12 - 3. current electricity
In a potentiometer arrangement, a cell gives a balancing point at \(75\, cm\) length of wire. This cell is now replaced by another cell of unknown emf. If the ratio of the emf's of two cells respectively is \(3: 2\), the difference in the balancing length of the potentiometer wire in above two cases will be.........\(cm .\)
- A \(25\)
- B \(255\)
- C \(95\)
- D \(27\)
Answer & Solution
Correct Answer
(A) \(25\)
Step-by-step Solution
Detailed explanation
\(\frac{\varepsilon_{1}}{\varepsilon_{2}}=\frac{\ell_{1}}{\ell_{2}}\) \(\frac{3}{2}=\frac{75 \,cm }{\ell_{2}}\) \(\ell_{2}=50\, cm\) \(\ell_{1}-\ell_{2}=75-50\) \(=25 \,cm\)
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