JEE Mains · Physics · STD 12 - Current electricity
- JEE Mains 2022
- Medium
- Numerical
A potentiometer wire of length \(10 \,m\) and resistance\(20 \,\Omega\) is connected in series with a \(25 \,V\) battery and an external resistance \(30\, \Omega\). A cell of emf \(E\) in secondary circuit is balanced by \(250\, cm\) long potentiometer wire. The value of \(E\) (in volt) is \(\frac{x}{10}\). The value of \(x\) is.......
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(25\)
Step-by-step Solution
Detailed explanation
\(I =\frac{25}{50}=\frac{1}{2} \,A\)
\(\therefore \Delta\, V =10 \,V\)
\(10 \,m \rightarrow 10 \,V\)
\(2.5\, m \rightarrow 2.5\, V\)
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