ELECTRIC CHARGES AND FIELDS Ch 1 Class 12th Physics

 Chapter-1

ELECTRIC CHARGES AND FIELDS

1.What does q1+q2=0 signify?

2.Define electric field intensity. Give its S.I. unit.

3. Define relative permittivity OR dielectric constant of a medium?

4.What is the formula for force experienced by a charge q placed in a uniform electric field E?

5.Electric field lines can not have a sudden break. Explain.

6.Define electric dipole moment. Write its S.I. unit.

7.Is electric dipole moment is a scalar or a vector? If it is a vector, then what is its direction?

8.In which orientation, a dipole placed in a uniform electric field is in (i) Stable equilibrium (ii) unstable equilibrium?

9.Define electric flux. Write its S.I. unit.

10.Draw the electric field lines due to a point charge Q when (i) Q>0 and (ii) Q<0.

11.Write any two basic properties of electric charges.

12.Write any two limitations of Coulomb’s law.

13.Write properties of electric field lines. Why do two electric field lines not intersect with each other?

14.State Gauss’s theorem in electrostatics. An electric dipole is inside the Gaussian surface. What is electric flux through the Gaussian surface? 

15.Show that net force on an electric dipole placed in a uniform electric field is zero. Find an expression for torque experienced by the electric dipole.

16.What is an electric dipole? Give an electric field sketch due to an electric dipole.

17.Find an expression for the electric field strength at any point on the (a) axial line of an electric dipole (b) Equatorial line.

18.State Gauss's theorem in electrostatics. Use it to derive an expression for an electric field at a point due to (a) an infinitely long, thin, uniformly charged straight wire (b) a uniformly charged infinite thin plane sheet.