An electric dipole of dipole moment p is placed in an electric field of intensity E such that angle between electric field and dipole moment is θθ. Assuming that the potential energy of the dipole is zero when θ=0°θ=0°, the potential energy of the dipole will be
1. -pE cosθθ
2. pE(1-cosθθ)
3. pE(cosθθ-1)
4. -2pE(cosθθ-1)
The electrostatic field due to a charged conductor just outside the conductor is:
1. | zero and parallel to the surface at every point inside the conductor. |
2. | zero and is normal to the surface at every point inside the conductor. |
3. | parallel to the surface at every point and zero inside the conductor. |
4. | normal to the surface at every point and zero inside the conductor. |
A charge q is to be divided on two small conducting spheres. What should be the value of charges on the spheres so that when placed at a certain distance apart, the repulsive force between them is maximum?
1. q4 and 3q4q4 and 3q4
2. q2 and q2q2 and q2
3. q3 and q3q3 and q3
4. q4 and q4q4 and q4
A particle having charge q1q1 exerts F electrostatic force on charge q2q2 at rest. If a particle having charge q14q14 is placed midway between the line joining the two charges q1 and q2q1 and q2 then electrostatic force on q2q2 due to q1q1 will become/remain
1. 2F
2. F2F2
3. F
4. zero
An electric dipole is in unstable equilibrium in the uniform electric field. The angle between its dipole moment and the electric field is
1. 90°°
2. 120°°
3. 0°°
4. 180°°
The law, governing the force between electric charges is known as
(1) Ampere's law
(2) Ohm's law
(3) Faraday's law
(4) Coulomb's law
Fg and Fe represents gravitational and electrostatic force respectively between electrons situated at a distance 10 cm. The ratio of Fg/ Fe is of the order of
(1) 1042
(2) 10
(3) 1
(4) 10–43
Four charges are arranged at the corners of a square ABCD,ABCD, as shown in the adjoining figure. The force on the positive charge QQ kept at the centre OO is:
1. | Zero | 2. | Along the diagonal ACAC |
3. | Along the diagonal BDBD | 4. | Perpendicular to side ABAB |
In the absence of other conductors, the surface charge density
(1) Is proportional to the charge on the conductor and its surface area
(2) Inversely proportional to the charge and directly proportional to the surface area
(3) Directly proportional to the charge and inversely proportional to the surface area
(4) Inversely proportional to the charge and the surface area
Out of gravitational, electromagnetic, Vander Waals, electrostatic and nuclear forces; which two are able to provide an attractive force between two neutrons
(1) Electrostatic and gravitational
(2) Electrostatic and nuclear
(3) Gravitational and nuclear
(4) Some other forces like Vander Waals