Question: Q. 3. What is Wheatstone bridge ? Deduce the condition for which Wheatstone bridge is balanced.
OR
The given figure shows a network of resistances $R_{1}, R_{2}, R_{3}$ and $R_{4}$.
Using Kirchhoff’s laws, establish the balance condition for the network.
OR
Use Kirchhoff’s law to obtain the balance condition for Wheastone bridge.
R&A [Delhi Comptt. I, II, III 2012]
$\begin{array}{ll}\text {
Show Answer
Solution:
Ans. (i) Definition of Wheatstone bridge } & \mathbf{1} \ \text { (ii) Expression }\end{array}$
(ii) Expression
[CBSE Marking Scheme 2012]
Detailed Answer :
(i) The Wheatstone bridge is an arrangement of four resistances. In this bridge, four resistances are connected on four arms of a quadrilateral. Across one diagonal, a battery and key are connected. Across second diagonal, a galvanometer is connected as shown in figure.
(ii) Try yourself Similar to Q. 2, Short Answer Type Questions-I
