A hollow copper sphere is positively charged. The electric field at its center will be
A. same as that on the surface
B. more than that on the surface
C. less than that on the surface nut not zero
D. zero
A. same as that on the surface
B. more than that on the surface
C. less than that on the surface nut not zero
D. zero
D. zero
A point charge +Q is placed in the vicinity of a conducting surface. Draw the electric field lines between the surface and the charge.
Derive an expression for electric field of a dipole at a point on the equatorial plane of the dipole. How does the field vary at large distances?
Three charges each equal to 2 μC are placed at the corners of an equilateral triangle. If force between any two charges is 2F, then the net force on either will be:
Figure shows a point charge + Q, located at a distance R/2 from the centre of a spherical metal shell. Draw the electric field lines for the given system.
The force between two charges, when placed in free space, is 5N. if they are in a medium of relative permittivity 5, the force between them will be
A. 1N
B. 25N
C. 2.5N
D. 1/5N
Two balls carrying charges - and +8 attract each other with a force F. If a charge of -3 is added to both the balls, then the force between then will become
A. 2F
B. F/2
C. F
D. zero
A parrot comes and sits on a bare high-power line. It will
A. experience a mild shock
B. experiences a strong shock
C. get killed instantaneously
D. not be affected at all
Electric charge between two bodies can be produced by
(A )Sticking
(B) Rubbing
(C) Oiling
(D) Passing AC current
the magnitude of a charge q at the center of two equal and like charges Q so that the three charges are in equilibrium
A. Q
B. Q/2
C. Q/4
D. –Q/4
Two point charges, \(q_1\) = 10 × \(10^{-8}\)C, \(q_2\) = -2 × \(10^{-8}\)C are seperated by a distance of 60 cm in air what is the electrostatic potential energy of the system.
1) 3 joule
2) -3 joule
3) -3 x\(10^{-5}\) joule
4) 3 x\(10^{-5}\) joule
A cylindrical bar magnet is rotated about its axis in the figure. A wire is connected from the axis and is made to touch the cylindrical surface through a contact. Then
In the diffraction pattern due to single slit, at the position of 2nd maximum the path difference between the wavelets from the opposite edges of the slit is
I. 5λ/2
II. 3λ/2
III. 2λ
IV. λ
When ordinary light is made incident on a quarter wave plate, the emergent light is
(a) linearly polarised.
(b) circularly polarised.
(c) unpolarised.
(d) elliptically polarised.
Ratio of intensities of two waves are given by 4 :1. Then the ratio of the amplitudes of the two waves.
(a) 2 : 1
(b) 1 : 2
(c) 4 : 1
(d) 1 : 4