Wheatstone bridge and metre bridge — practice questions

Question 1 · difficulty L2 · understanding

The value of current I in the electrical circuit as given below, when potential at A is equal to the potential at B, will be _______ A.

Question 2 · difficulty L2 · understanding

The value of unknown resistance $$(x)$$ for which the potential difference between $$B$$ and $$D$$ will be zero in the arrangement shown, is :

• A. 3 $$\Omega$$
• B. 42 $$\Omega$$
• C. 6 $$\Omega$$
• D. 9 $$\Omega$$

Question 3 · difficulty L2 · understanding

The equivalent resistance between $$A$$ and $$B$$ of the network shown in figure;

• A. 21 R
• B. $$\frac{8}{3}$$ R
• C. 11$$\frac{2}{3}$$ R
• D. 14 R

Question 4 · difficulty L2 · understanding

A battery of $$6 \mathrm{~V}$$ is connected to the circuit as shown below. The current I drawn from the battery is :

• A. 1A
• B. 2A
• C. $$\frac{6}{11}$$ A
• D. $$\frac{4}{3}$$ A

Question 5 · difficulty L2 · understanding

The current I in the given circuit will be :

• A. 10 A
• B. 20 A
• C. 4 A
• D. 40 A

Question 6 · difficulty L2 · understanding

In a meter bridge experiment, for measuring unknown resistance 'S', the null point is obtained at a distance $$30 \mathrm{~cm}$$ from the left side as shown at point D. If R is $$5.6$$ $$\mathrm{k} \Omega$$, then the value of unknown resistance 'S' will be __________ $$\Omega$$.

Question 7 · difficulty L2 · understanding

A meter bridge setup is shown in the figure. It is used to determine an unknown resistance R using a given resistor of 15 $$\Omega$$. The galvanometer (G) shows null deflection when tapping key is at 43 cm mark from end A. If the end correction for end A is 2 cm, then the determined value of R will be ____________ $$\Omega$$.

Question 8 · difficulty L2 · understanding

STATEMENT - 1 In a Meter Bridge experiment, null point for an unknown resistance is measured. Now, the unknown resistance is put inside an enclosure maintained at a higher temperature. The null point can be obtained at the same point as before by decreasing the value of the standard resistance. and STATEMENT - 2 Resistance of a metal increases with increase in temperature.

• A. Statement - 1 is True, Statement - 2 is True; Statement - 2 is a correct explanation for Statement - 1
• B. Statement - 1 is True, Statement - 2 is True; Statement - 2 is NOT a correct explanation for Statement - 1
• C. Statement - 1 is True, Statement - 2 is False
• D. Statement - 1 is False, Statement - 2 is True

Question 9 · difficulty L3 · understanding

If the potential difference between $\mathrm{B}$ and $\mathrm{D}$ is zero, the value of $x$ is $\frac{1}{n} \Omega$. The value of $n$ is __________.

Question 10 · difficulty L3 · understanding

In the balanced condition, the values of the resistances of the four arms of a Wheatstone bridge are shown in the figure below. The resistance R 3 has temperature coefficient 0.0004$$^\circ$$C -1 . If the temperature of R 3 is increased by 100$$^\circ$$C, the voltage developed between S and T will be ________ volt.