# Wheatstone Bridge

## Trending Questions

**Q.**A, B and C are three points situated in a uniform electric field, as shown. The electric potential is-

- Same at all the three points A, B and C
- Maximum at A
- Maximum at B
- Maximum at C

**Q.**In a potentiometer experiment, it is found that no current passes through the galvanometer when the terminals of the cell are connected across 52 cm of the potentiometer wire. If the cell is shunted by the resistance of 5 Ω, a balance is found when the cell is connected across 40 cm of the wire. Find the internal resistance of the cell.

- 2Ω
- 2.5Ω
- 1Ω
- 1.5Ω

**Q.**

What is current sensitivity?

**Q.**In the following circuit, the resultant capacitance between A and B is 1 μF. Then the value of C is 32x μF

**Q.**The metre bridge is in balance position with P/Q=l1/l2 if yes now interchange the position of galvanometer and cell will the bridge work?if yes what will be the balanced condition

**Q.**Twelve capacitors each having a capacitance C, are connected to form a cube. Find the equivalent capacitance of the cube along the face diagonal?

[Take C=9 μF]

- 43 μF
- 127 μF
- 12 μF
- 56 μF

**Q.**The equivalent capacitance between points A and B is-

- C4
- C2
- C
- 2C

**Q.**

Define analog device and give some examples of it

**Q.**Four identical capacitors are connected as shown in diagram. When a battery of 6 V is connected between A and B, the charge stored is found to be 1.5 μC. The value of C1 is: -

- 2.5 μF
- 15 μF
- 1.5 μF
- 0.1 μF

**Q.**Twelve capacitors each of capacitance C are connected together so that each lies along the edge of the cube as shown in figure. The equivalent capacitance between 1 and 4 will be:

- 5C7
- 4C3
- 12C7
- 7C4

**Q.**

Why shunt is connected in parallel to galvanometer?

**Q.**Three capacitors connected in series have an effective capacitance of 2 μF. If one of the capacitors is removed, the effective capacitance becomes 3 μF. The capacitance of the capacitor that is removed is

- 13 μF
- 32 μF
- 23 μF
- 6 μF

**Q.**What is the equivalent capacitance of the infinite ladder network shown in figure between points A and B.

- 43 μF
- 23 μF
- Infinite
- (1+√3) μF

**Q.**

How does the meter bridge overcome end error?

**Q.**A number of capacitors each of capacitance 1 μF and each one of which gets damaged if the potential difference just exceeding 500 V is applied. Then an arrangement suitable for giving a capacitor of capacitance 3 μF across which 2000 V may be applied, requires at least _____ capacitors. (Give integer value)

**Q.**An ammeter and a milliammeter are converted from the galvanometer. Out of the two, Which current

measuring instrument has higher resistance?

**Q.**In a PNP transistor working as a common-base amplifier, current gain is 0.96 and emitter current is 7.2 mA. The base current is

- 0.4 mA
- 0.2 mA
- 0.29 mA
- 0.35 mA

**Q.**15. The rms value of current for an a.c. current given by I= 4+3cos(ω t) is(1) 5A(2) 4.53 A(3) 4.17 A(4) 4.23 A

**Q.**The effective resistance between points P and Q of the electric circuit shown in the figure is?

- 8(R+r)(3R+r)

- 2Rr(R+r)

- 2r+4R
- 2.5R+2r

**Q.**An infinite number of identical capacitors each of capacitance 1μF are connected as shown in the adjoining figure. Then, equivalent capacitance between A and B is

- Infinite
- 2μF
- 4μF
- 8μF

**Q.**

Why should we get the null point in the middle of the Meter bridge wire?

**Q.**Three capacitors having capacitance 20 μF, 30 μF and 40 μF are connected in series with a 12 V battery. The amount of work done by the battery in charging the combination will be:

- 1.5×10−3 J
- 2.25×10−3 J
- 1.33×10−3 J
- 3×10−3 J

**Q.**

In a Wheatstone bridge, all four arms have equal resistance $r$. If the resistance of the galvanometer arm is also $r$, the equivalent resistance of the combination as seen by the battery is

$\frac{r}{4}$

$\frac{r}{2}$

$r$

$2r$

**Q.**Two cells of e.m.f E1 and E2 (E1>E2) are connected as shown in figure. When a potentiometer is connected between A and B, the balancing length of the potentiometer wire is 300 cm. On connecting the same potentiometer between A and C, the balancing length is 100 cm. The ratio E1/E2 is

- 3:1
- 1:3
- 2:3
- 3:2

**Q.**

In the given circuit, it is observed that the current $I$ is independent of the value of resistance ${R}_{6}$ . Then the resistance values must satisfy the condition

${R}_{1}{R}_{2}{R}_{5}={R}_{3}{R}_{4}{R}_{6}$

$\frac{1}{{R}_{3}}+\frac{1}{{R}_{6}}=\frac{1}{{R}_{1}{R}_{2}}+\frac{1}{{R}_{1}{R}_{4}}$

${R}_{1}{R}_{4}={R}_{2}{R}_{3}$

${R}_{1}{R}_{3}={R}_{2}{R}_{4}={R}_{5}{R}_{6}$

**Q.**The effective capacitance of the given network across AB is

- 289 μF
- 4μF
- 5μF
- 18μF

**Q.**Resistances are connected in a meter bridge circuit as shown in the figure. The balancing length l1 is 40 cm. Now an unknown resistance x is connected in series with P and new balancing length is found to be 80 cm measured from the same end. Then the value of x will be

**Q.**Five resistances are combined according to the figure. The equivalent resistance between the point X and Y will be

- 10 Ω
- 22 Ω
- 20 Ω
- 50 Ω

**Q.**Four resistances are connected in a circuit as shown in the figure. The electric current flowing through 4 Ω and 6 Ω resistance respectively will be

- 2 A and 4 A
- 1 A and 2 A
- 21 A and 2 A
- 2 A and 2 A

**Q.**What is the capacitance between points A and B for the given assembly?

- 2.5μF
- 5μF
- 1.25μF
- 2.25μF