CBSE PHYSICS IMPORTANT QUESTIONS CLASS 12 CHAPTER 1 ELECTRIC CHARGES AND FIELDS

           JAWAHAR NAVODAYA VIDYASLAYA WESTSINGHBHUM

                            CLASS 12 (2021-22)    SUMMER HOME ASSIGNMENT                                      

  Electric charges and fields

For video lectures click below links 

Link for short videos full chapter in 2hrs

 https://youtube.com/playlist?list=PLjIA_RjrRWb12L9_Kg2KmqVRII5Zl9ITE

Link for detailed lectures of electric charges and fields

https://youtube.com/playlist?list=PLjIA_RjrRWb1N_7w3gJbCB6yYwWu38Piv

List of important questions

1. State Coulomb's law and express it in vector form.

2.Defien electric dipole moment and write its SI unit

3. Define electric field intensity and derive expression due to electric field due to point charge

4. Derive an expression for the electric field at a point on the axial position of an electric dipole.

Give its direction

5. Derive an expression for the electric field at a point on the equatorial position of an electric dipole. Give its direction

6. (i) An electric dipole is held in a uniform electric field. Using suitable diagram show that it does not undergo any translatory motion. Derive the expression for the force and torque acting on it.

 (ii) What would happen if the field in non-uniform electric field?

 (iii) What would happen if the external electric field is increasing (Non uniform electric field)

 (a) parallel to and (b) anti-parallel to?

7. Define electric flux write its SI unit

8. Define electric field line, Write their properties

9. Derive an expression for the Net force and torque on an electric dipole in a uniform electric field.

10. Derive an expression for the work done in rotating an electric dipole in a uniform electric field

11. Derive an expression for the energy stored (Potential Energy) in a dipole in a uniform electric field. State conditions for stable and Unstable equilibrium of electric dipole in uniform electric field

12. State and prove gauss law

13. State Gauss theorem and apply it to find the electric field at a point due to infinite straight charged wire of linear density 
14. Using Gauss’s law, obtain the expression for electric field intensity at a point due to an infinitely large, plane sheet of charge of charge density σ C/m². How is the field directed if the sheet is

(i) positively charged (ii) negatively charged?

15. Using Gauss’s law, deduce the expression for the electric field due to uniformly charged spherical conducting shell of radius at a point (i) outside and (ii) inside the shell. Plot a graph showing variation of electric field as a function of r > R and r< R.