Question 14: Current Electricity

Question

The effective resistance between p and q in
given figure is

Accepted Answer

Figure is equivalent to the one shown
below.
It is a WheatstoneÃ¢ÂÂs bridge in which
$$\begin{aligned}
& P=\frac{6 	imes 3}{6+3}=2 \Omega \\
& Q=\frac{8}{2}=4 \Omega \\
& R=\frac{4}{2}=2 \Omega 	ext { and } S=\frac{20 	imes 5}{20+5}=4 \Omega
\end{aligned}$$
We find that $$\frac{P}{Q}=\frac{2}{4}=\frac{R}{S}$$
i.e. the bridge is balanced. Effective resistance between $$p$$ and $$q$$
$$\begin{aligned}
R_{A B} & =\frac{(P+Q)(R+S)}{P+Q+R+S}=\frac{(2+4)(2+4)}{2+4+2+4} \\
& =\frac{6 	imes 6}{12}=3 \Omega
\end{aligned}$$

Answer

2$$\Omega$$

Answer

3$$\Omega$$

Answer

5$$\Omega$$

Answer

6$$\Omega$$

Current Electricity

The effective resistance between p and q in given figure is

Choose the correct answer: