Question

In a Wheatstone bridge P = 10$\Omega$, Q = 20$\Omega$,R=30$\Omega$. The value of 'S' in order that no current flows through the galvanometer is :

• A. 15$\Omega$
• B. 45$\Omega$
• C. 30$\Omega$
• D. 60$\Omega$

Answer 1

Answer: (D)

60$\Omega$

by applying Wheatstone bridge condition:

$\frac{P}{Q}=\frac{R}{S}$

now putting all the values given in question we get;
$\Rightarrow \frac{10}{20}=\frac{30}{S}$
$\Rightarrow S=60\Omega$