Question 603: Current Electricity

Question

A potentiometer wire is $$4 \mathrm{~m}$$ long and potential difference of $$3 \mathrm{~V}$$ is maintained between the ends. The emf of the cell, which balances against a length of $$100 \mathrm{~cm}$$ of the potentiometer wire is

Accepted Answer

The arrangement of potentiometer is shown below
When the potentiometer is in balanced condition, Potential difference across $$A J=$$ Potential difference across $$A E J$$
$$\Rightarrow \quad \frac{V}{L} 	imes I=E$$
$$	herefore$$ emf of cell, $$E=\frac{3}{400} 	imes 100=\frac{3}{4}=0.75 \mathrm{~V}$$

Answer

0.60 V

Answer

0.50 V

Answer

0.25 V

Answer

0.75 V

Current Electricity

A potentiometer wire is $4 \mathrm{~m} long and potential difference of 3 \mathrm{~V} is maintained between the ends. The emf of the cell, which balances against a length of 100 \mathrm{~cm}$ of the potentiometer wire is

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