Question 1

The potential difference  (V_A-V_B)  between the points A and B in the given figure is.

Accepted Answer

Given :    I = 2  A           Using Kirchhoff's law        V_A  - I(2) - 3 - I(1) - V_B = 0 	herefore      V_A - 2	imes 2 - 3  - 2	imes 1 -V_B = 0              OR      V_A - 9 - V_B = 0                 \implies V_A - V_B = +9  V

Question 2

State and explain Kirchhoff's Laws in the current electricity.

Accepted Answer

Kirchhoff's laws: (i) The algebraic sum of current meeting at an junction in a circuit is zero. In this law, the current flowing towards the junction are considered as  + ve and those flowing away from the junction as  - ve currents.As shown in the figure, we have      {i}_{1} - {i}_{2} - {i}_{3} + {i}_{4} - {i}_{5} = 0 or   {i}_{1} + {i}_{4} = {i}_{2} + {i}_{3} + {i}_{5} (ii) In any closed mesh (or loop) of an electrical circuit, be algebraic sum of the product of the currents and resistances is equal to the total e.m.f. of the mesh.     If we go along the direction of conventional current, be potential difference will be taken as negative and opposite to it will be positive.    Inside the cell, if we move from low to high potential along the direction of conventional current the e.m.f. will be positive.For loop 1,           {E}_{2} - {i}_{2}{R}_{2} - \left({i}_{1} + {i}_{2}\right) {R}_{3} = 0 or        {E}_{2} = {i}_{2}{R}_{2} + \left({i}_{1} + {i}_{2}\right) {R}_{3} For loop 2,          {i}_{2}{R}_{2} - {E}_{2} - {i}_{1}{R}_{1} + {E}_{1} = 0 or       {E}_{1} - {E}_{2} = {i}_{1}{R}_{1} - {i}_{2}{R}_{2}

Question 3

Kirchoffs 1st and 2nd laws are based on conservation of

Accepted Answer

Kirchhoff's  1 st law states that the total amount of current coming at a junction must be equal to the total amount of current going away from it i.e. the total charge must be conserved. Thus Kirchhoff's  1 st law is based on the conservation of charge.Kirchhoff's  2 nd law states that the sum of the potential drop across all the components in a loop must be zero. Thus Kirchhoff's  2 nd law is based on the conservation of energy.

Question 4

The figure below shows currents in a part of electric circuit. The current   i   is

Accepted Answer

According to Kirchhoff's first lawAt junction  A, i_{AB}=2+2=4\ A At junction  B, i_{AB}=i_{BC}-1=3\ A At junction  C, i=i_{BC}-1.3=3-1.3=1.7\ amp

Question 5

Determine the current in each branch of the network shown in Fig.

Accepted Answer

Toppr Ask Answer

Question 6

In the circuit shown, the value of currents  I_1, I_2  and  I_3  are.

Accepted Answer

Applying Kirchoff's voltage law, In loop.  I    = -27 -6I_2 - 2I_1 + 24 = 0 \Rightarrow 6I_2 + 2I_1 = -3      ...(1)In loop-  II -27 - 6I_2 + 4I_3 = 0 6I_2 - 4I_3 = -27       ...(2)Junction ' p ' I_1 = I_2 + I_3       ...(3)Solving equation (1), (2) and (3) we get, I_1 = 3A, \,I_2 = -3/2 A, \,I_3 = 9/2A

Question 7

A switch S is closed in the circuit shown in figure, current passed through point A is?

Accepted Answer

Toppr Ask Answer

Question 8

State Kirchoff's current law and also give the sign convention for current.

Accepted Answer

Kirchhoff's current law states that at any node(junction) in an electric circuit, the sum currents flowing in to that node is equal to the sum of current flowing out of that node.Sign convention:- current entering at any junction is considered as positive.                        and current leaving the junction is considered as negative.In given circuit,By Kirchhoff's current law, i_2+i_3=i_1+i_4

Question 9

Consider the circuit shown in the figure. The current  I_3  is equal to

Accepted Answer

Suppose current through different paths of the circuit is as follows.After applying  KVL , for loop (1) and (2)We get  28i_1=-6-8\Rightarrow i_1=-\dfrac 12\ A and  54i_2=-6-12\Rightarrow i_2=-\dfrac 13\ A Hence  i_3=i_1+i_2=-\dfrac 56\ A

Question 10

Kirchhoff s junction rule is a reflection of

Accepted Answer

According to junction rule, the algebraic sum of current or charge flowing per unit time towards a junction in an electric network is zero, i.e., the law of conservation of charge verifies answer (b) and no any charges accumulate at junction as the sum of entering and outgoing charge are equal, at any time interval. It verifies answer (d).

Revise with Concepts

Kirchoff's Law

Learn with Videos

Quick Summary With Stories

Kirchhoff's Voltage Law

Conservation of Energy by Kirchoff's Law

Problems based on Kirchhoff's law

Important Questions

The potential difference $(V_{A} - V_{B})$ between the points A and B in the given figure is.

State and explain Kirchhoff's Laws in the current electricity.

Kirchoffs 1st and 2nd laws are based on conservation of

The figure below shows currents in a part of electric circuit. The current $i$ is

Determine the current in each branch of the network shown in Fig.

In the circuit shown, the value of currents $I_{1}, I_{2}$ and $I_{3}$ are.

A switch S is closed in the circuit shown in figure, current passed through point A is?

State Kirchoff's current law and also give the sign convention for current.

Consider the circuit shown in the figure. The current $I_{3}$ is equal to

Kirchhoff s junction rule is a reflection of

Revise with Concepts

Kirchoff's Law

Learn with Videos

Quick Summary With Stories

Kirchhoff's Voltage Law

Conservation of Energy by Kirchoff's Law

Problems based on Kirchhoff's law

Important Questions

The potential difference (VA​−VB​) between the points A and B in the given figure is.

State and explain Kirchhoff's Laws in the current electricity.

Kirchoffs 1st and 2nd laws are based on conservation of

The figure below shows currents in a part of electric circuit. The current i is

Determine the current in each branch of the network shown in Fig.

In the circuit shown, the value of currents I1​,I2​ and I3​ are.

A switch S is closed in the circuit shown in figure, current passed through point A is?

State Kirchoff's current law and also give the sign convention for current.

Consider the circuit shown in the figure. The current I3​ is equal to

Kirchhoff s junction rule is a reflection of

The potential difference $(V_{A} - V_{B})$ between the points A and B in the given figure is.

The figure below shows currents in a part of electric circuit. The current $i$ is

In the circuit shown, the value of currents $I_{1}, I_{2}$ and $I_{3}$ are.

Consider the circuit shown in the figure. The current $I_{3}$ is equal to