Question 572: Current Electricity

Question

In the following network, the current through galvanometer will

Accepted Answer

This is an unbalanced network.
Current through the branch PQR is $$\mathrm{I}_1=\frac{\mathrm{V}}{8}$$ and current through the branch $$\mathrm{PSR}=\mathrm{I}_2=\frac{\mathrm{V}}{4}$$
$$\begin{aligned}
& 	herefore \mathrm{V}_{\mathrm{P}}-\mathrm{V}_{\mathrm{Q}}=\mathrm{I}_1 	imes 4=\frac{\mathrm{V}}{8} 	imes 4=\frac{\mathrm{V}}{2} \
& 	ext { and } \mathrm{V}_{\mathrm{P}}-\mathrm{V}_{\mathrm{S}}=\mathrm{I}_2 	imes 1=\frac{\mathrm{V}}{4} 	imes 1=\frac{\mathrm{V}}{4} \
& 	herefore\left(\mathrm{V}_{\mathrm{P}}-\mathrm{V}_{\mathrm{Q}}ight)-\left(\mathrm{V}_{\mathrm{P}}-\mathrm{V}_{\mathrm{S}}ight)=\frac{\mathrm{V}}{2}-\frac{\mathrm{V}}{4}=\frac{\mathrm{V}}{4} \
& 	herefore \mathrm{V}_{\mathrm{S}}-\mathrm{V}_{\mathrm{Q}}=\frac{\mathrm{V}}{4} \
& 	herefore \mathrm{V}_{\mathrm{S}}>\mathrm{V}_{\mathrm{Q}}
\end{aligned}$$
$$	herefore$$ The current will flow from $$\mathbf{S}$$ to $$\mathbf{Q}$$.

Answer

be zero

Answer

flow from $$\mathrm{Q}$$ to $$\mathrm{S}$$

Answer

flow in a direction which depends on value of $$\mathrm{V}$$

Answer

flow from $$\mathrm{S}$$ to $$\mathrm{Q}$$

Current Electricity

In the following network, the current through galvanometer will

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