Question 303: Current Electricity

Question

A potentiometer wire AB having length L and resistance 12 r is joined to a cell D of emf $$\varepsilon $$ and internal resistance r. A cell C having emf $$\varepsilon $$/2 and internal resistance 3r is connected. The length AJ at which the galvanometer as shown in figure shows no deflection is –

Accepted Answer

$$i = {\varepsilon  \over {13r}}$$
$$i\left( {{x \over L}12r} \right) = {\varepsilon  \over 2}$$
$${\varepsilon  \over {13r}}\left[ {{x \over L}.12r} \right] = {\varepsilon  \over 2}$$
$$ \Rightarrow \,\,\,\,x = {{13L} \over {24}}$$

Answer

$${{11} \over {12}}L$$

Answer

$${{13} \over {24}}L$$

Answer

$${{5} \over {12}}L$$

Answer

$${{11} \over {24}}L$$

Current Electricity

A potentiometer wire AB having length L and resistance 12 r is joined to a cell D of emf $\varepsilon and internal resistance r. A cell C having emf \varepsilon $/2 and internal resistance 3r is connected. The length AJ at which the galvanometer as shown in figure shows no deflection is –

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