Choose the SI unit of electric potential energy :
(a) Joule
(b) Coulomb
(c) Newton per coulomb
(d) Erg
(a) Joule
(b) Coulomb
(c) Newton per coulomb
(d) Erg
(a) Joule
The electric potential due to point charge 3 nC at distance of 9 cm is
(a) 270 v
(b) 3 v
(c) 300 v
(d) 30 v
Why are electric field lines perpendicular at a point on an equipotential surface of a conductor ?
For any charge configuration, equipotential surface through a point is normal to the electric field. Justify.
What is the effect on the angular width of interference fringes in a Young’s double slit experiment when the screen moved near to the plane of slits.
(a) increases
(b) decreases
(c) constant
(d) not defined
The ratio of magnetic length to geometric length of a magnet is
a) 0.084
b) 8.4
c) 80.4
d) 0.84
A dip circle is so set that it moves freely in the magnetic meridian. The angle of dip is 40°. Now the dip circle is rotated so that the plane in which the needle moves makes an angle of 30° with the magnetic meridian. In this position, the needle will dip by the angle
Which of the following is conserved when light waves interference?
(a) phase.
(b) intensity.
(c) amplitude.
(d) none of these.
The angle of incidence at which reflected light is totally polarised for reflection from air to glass (refractive index n) is
Two copper spheres of the same radius, one solid and the other hollow, are charged to the same potential. Which will have more charge?
(a) Solid sphere
(b) Hollow sphere
(c) Both will have an equal charge
(d) None of these
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.