HARD
12th Rajasthan Board
IMPORTANT
Earn 100

Explain the concept of electric field. Express electric flux through a surface in terms of electric field intensity. Show that the electric flux through a cylindrical surface with its axis parallel to a uniform electric field is zero.

Important Questions on Electric Charges and Fields
HARD
12th Rajasthan Board
IMPORTANT
An electric dipole is formed by two charges and placed at the two ends of an insulating rod of length and negligible mass. Write down the dipole moment. Is it a vector or a scalar? The dipole is then placed in a uniform electric field and is given a small angular displacement from its equilibrium position. What are the total force and torque acting on it?

EASY
12th Rajasthan Board
IMPORTANT
Name the basic properties of electric charge.

HARD
12th Rajasthan Board
IMPORTANT
There are four charges, each with a magnitude . Two are positive and two are negative. The charges are fixed to the corners of a square of side , one to each corner, in such a way that the force on any charge is directed toward the center of the square. Find the magnitude of the net electric force experienced by any charge?

HARD
12th Rajasthan Board
IMPORTANT
Two identical conducting spheres, having charges of opposite sign attract each other with a force of when separated by . The spheres are now connected by a conducting wire. When the wire is removed, spheres repel each other with a force of . What were the initial charges on the spheres?

EASY
12th Rajasthan Board
IMPORTANT
Under the action of a given coulombic force, the acceleration of an electron is . Then the acceleration of a proton due to the same force is nearly

MEDIUM
12th Rajasthan Board
IMPORTANT
How many electrons should be removed from a coin of mass , so that it may float in an electric field of intensity directed upward

EASY
12th Rajasthan Board
IMPORTANT
Some point charges are placed on the circumference of circle at equal distance (see figure). The direction of electric field at centre will be along

EASY
12th Rajasthan Board
IMPORTANT
The true physical significance of the electric field emerges when we deal with the _____ electromagnetic phenomenon.
