Question 564: Current Electricity

Question

In meter bridge experiment, null point was obtained at a distance '$$l$$' from left end. The values of resistances in the left and right gap are doubled and then interchanged. The new position of the null point is

Accepted Answer

For a Metre bridge,
$$\frac{\mathrm{X}}{\mathrm{R}}=\frac{l_{\mathrm{X}}}{l_{\mathrm{R}}}$$
After doubling and interchanging the left and right gap resistances, the ratio of the resistances do not change.
This means the null point does not change.
$$	herefore \quad$$ The new position will remain at $$(100-l)$$.

Answer

$$(100-l)$$

Answer

$$(100-2 l)$$

Answer

$$(100-3 l)$$

Answer

$$\left(100-\frac{l}{2}\right)$$

Current Electricity

In meter bridge experiment, null point was obtained at a distance '$l$' from left end. The values of resistances in the left and right gap are doubled and then interchanged. The new position of the null point is

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