Establish an expression for the electric field at a point along the axial line of an electric dipole.

Let P be an axial point at distance r from the centre of the dipole. Electric potential at point P is given as V = V 1 + V 2 V 1 and V 2 are the potentials at point P due to charges + q and - q respectively. V = 1 4 πε o q r - 2 a + - q r + 2 a V = 1 4 πε o 4 a r 2 - 4 a 2 V = 1 4 πε o 2 P r 2 - 4 a 2 Hence,the electric potential is 1 4 πε o 2 P r 2 - 4 a 2 .

E M B I B E

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 1 - Electric Charges and Fields>Nagaland Board-2018>Q 2

EASY

12th Nagaland Board

IMPORTANT

Earn 100

Using Gauss theorem, deduce an expression for the electric field at a point due to a uniformly charged infinite plane sheet.

Important Questions on Electric Charges and Fields

EASY

12th Nagaland Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 1 - Electric Charges and Fields>Nagaland Board-2019>Q 3

A charge

q

is enclosed by a Gaussian spherical surface of radius

R

. If the radius is doubled, then the outward electric flux will

HARD

12th Nagaland Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 1 - Electric Charges and Fields>Nagaland Board-2019>Q 4

State Coulomb’s law of electrostatic. Show that the electrostatic forces between two static charges separated by a distance follow Newton’s third law of motion.

EASY

12th Nagaland Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 1 - Electric Charges and Fields>Nagaland Board-2020>Q 5

Derive an expression for the torque experienced by an electric dipole kept in a uniform electric field.