# Kirchhoff's Junction Law

## Trending Questions

**Q.**A short electric dipole has a moment of 16×10−9 Cm. The electric potential due to the dipole at a point at distance of 0.6 m from the centre of the dipole, situates on a line making an angle of 60∘ with the dipole axis is

- Zero
- 50 V
- 200 V
- 400 V

**Q.**An ac circuit has an inductor and a resistor of resistance R in series, such that XL=3R. Now, a capacitor is added in series such that XC=2R. The ratio of new power factor with the old power factor of the circuit is √5:x. The value of 9x is ______.

**Q.**

In the figure shown, the current in the 10 V battery is close to

$0.21A$ from positive to the negative terminal

$0.36A$ from negative to the positive terminal

$0.42A$ from positive to the negative terminal

$0.71A$ from positive to the negative terminal

**Q.**The primary of a transformer when connected to a dc battery of 10 V draws a current of 1 mA. The number of turns of the primary and secondary windings are 50 and 100 respectively. The voltage in the secondary and the current drawn by the circuit in the secondary are respectively

- 20 V and 2.0 mA
- 10 V and 0.5 mA
- Zero volt and therefore no current
- 20 V and 0.5 mA

**Q.**

Two resistors X and Y of resistances $2\text{ohm}$ and $3\text{ohm}$ respectively are first joined in parallel and then in series. In each case, the voltage supplied is $5\text{V}$.

(i) Draw the circuit diagram to show the combination of resistors in the parallel connection.

(ii) Calculate the voltage across the $3\text{ohm}$ resistor in the series combination of resistors.

**Q.**Determine the current in the following circuit

- 1 A
- 2.5 A
- 0.4 A
- 3 A

**Q.**The given four terminal network is part of a larger circuit. The points A, B, C are at the same potential. The potential difference between any one of A, B or C and D is 40 V. The potential difference between A and O is

- 10 V
- 15 V
- 18 V
- 20 V

**Q.**Three resistance are joined to form a letter Y, as shown in figure. If the potentials of the terminals A, B and C are 6 V, 3 V and 2 V respectively, then the potential of the point O will be

- 4 V
- 3 V
- 2.5 V
- 0 V

**Q.**

Kirchhoffs first law is based on?

**Q.**The magnitude of i in ampere unit is

- None of these
- 0.1
- 0.3
- 0.6

**Q.**Explain why electric current is not a vector quantity.

**Q.**The figure shows a network of currents. The magnitude of current is shown here. The current i will be

- 23 A
- – 3 A
- 3 A
- 13 A

**Q.**Two batteries with e.m.f 12 V and 13 V are connected in parallel across a load resistor of 10 Ω. The internal resistance of the two batteries are 1 Ω and 2 Ω respectively. The voltage across the load lies between

- 11.4 V and 11.5 V
- 11.7 V and 11.8 V
- 11.6 V and 11.7 V
- 11.5 V and 11.6 V

**Q.**Two identical capacitors A and B, charged to the same potential of 5 V each, are connected in two different circuits, as shown below, at the time instant t=0. If the charge on capacitors A and B at time t=CR, is QA and QB respectively, then (Here, e is the base of natural logarithm.)

- QA=CVe, QB=CV2
- QA=CV, QB=CV
- QA=CV, QB=CVe
- QA=CV2, QB=CVe

**Q.**The n row each containing m cells in series are joined in parallel. Maximum current is taken from this combination across an external resistance of 3 Ω resistance. If the total number of cells used are 24 and internal resistance of each cell is 0.5 Ω, then

- m=8, n=3
- m=6, n=4
- m=12, n=2
- m=2, n=12

**Q.**The value of V0 in the following diagram is

- 4V
- 6V
- 8V
- 10V

**Q.**A part of a complete circuit is shown in the figure. At some instant, the value of current I is 1 A and it is decreasing at a rate of 102 As−1. The value of the potential difference (VP−VQ) ( in volts ) at that instant, is

**Q.**Which of the following equations is a correct equation for the electrical circuit shown in the figure?

- ε1−(i1+i2)R−i1r1=0
- ε2−i2r2−ε1−i1r1=0
- −ε2−(i1+i2)R+i2r2=0
- ε1−(i1+i2)R+i1r1=0

**Q.**A circuit has a section AB as shown in figure. If VA−VB=20 V, then the potential difference across capacitors C1 and C2 are respectively

- 5 V and 10 V
- 10 V and 5 V
- 20 V and 10 V
- 10 V and 20 V

**Q.**The given infinite grid consists of hexagonal cells of six resistors each of resistance R. Then R12 is equal to

- R3
- 2R3
- 4R3
- 3R4

**Q.**

How is potential gradient measured?

**Q.**

There are $10$ lamps in a hall.

Each one of them can be switched on independently.

The number of ways in which the hall can be illuminated is?

$102$

$1023$

$210$

$10!$

**Q.**A short electric dipole has dipole moment of 2.4×10–10 C-m. The electric potential due to the dipole at a point at a distance of 0.4 m from the centre of the dipole situated on a line making an angle 60∘ with the dipole axis is -

- 3.25 V
- 4.55 V
- 6.75 V
- 12.50 V

**Q.**Each resistance of the circuit shown in diagram is r. The equivalent resistance across the points A and B is

- r
- r4
- r2
- 5r8

**Q.**Two identical parallel plate capacitors are placed in series and connected to a constant voltage source of V0 volt. If one of the capacitors is completely immersed in a liquid with dielectric K, the potential difference between the plates of the other capacitor will change to KK+nV0, then find the value of n.

**Q.**An inductance L and a resistance R are first connected to a battery. After attaining steady state, the battery is disconnected but L and R remain connected in a closed circuit. Then, the current reduces to 37% of its initial value in time -

- RL
- RL
- LR
- 1LR

**Q.**Figure shows a meter bridge wire AC with a uniform cross-section. The length of wire AC is 100 cm. X is a standard resistor of 4 Ω and Y is a coil. When Y is immersed in melting ice the null point is at 40 cm from point A. When the coil Y is heated to 100∘ C, a 12 Ω resistor has to be connected in parallel with Y in order to keep the bridge balanced at the same point. The temperature coefficient of resistance of the coil Y is x×10−2. The value of x is

**Q.**In the circuit shown in figure, cells of emf 2, 1, 3 and 1 V, respectively and resistances 2 Ω, 1 Ω, 3 Ω and 1 Ω are their internal resistances respectively. The potential difference between D and B is given as n13 volts. Find n.

**Q.**Three capacitors of capcitances 3 μF, 4 μF and 6 μF are charged upto a potential difference of 2V, 3V and 4V respectively. If terminal a is connected with f, terminal e is connected with d and c is connected with b then find the charge flowing through the circuit?

- 24 μC
- 12 μC
- 16 μC

- 9 μC

**Q.**The four charges -q, -2q, -q, and 4q are placed on four verticers A, B, C and D of a square respectively. Calculate the dipole moment of the system