CUET Preparation Today
A cell having emf $\varepsilon$ and internal resistance r is connected across a variable external resistance R. When the resistance R keeps on increasing the graph of potential difference V across the R will be: |
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The correct answer is Option (3).
$V=\left(\frac{ε}{R+r}\right)=R=\frac{ε}{1+\frac{R}{r}}$ $∴R=∞,V=ε$ |
