In a region of constant potential,
(a) the electric field is uniform
(b) the electric field is zero
(c) there can be no charge inside the region
(d) the electric field shall necessarily change, if a charge is placed outside the region
(a) the electric field is uniform
(b) the electric field is zero
(c) there can be no charge inside the region
(d) the electric field shall necessarily change, if a charge is placed outside the region
(b) the electric field is zero
A dielectric induces....... in an external electric field which decreases the net electric field.
(a) current
(b) dipole moment
(c) magnetic field
(d) polarisation
(i) Derive the expression for the electric potential due to an electric dipole at a point on its axial line.
(ii) Depict the equipotential surface due to electric dipole.
Draw a plot showing the variation of (i) electric field (E) and (ii) electric potential (V) with distance r due to a point charge Q.
Two point charges q and –2q are kept d distance apart. Find the location of the point relative to charge q at which potential due to this system of charges is zero.
Derive an expression for potential due to a dipole for distances large compared to the size of the dipole. How is the potential due to dipole different from that due to single charge ?
The electric potential of earth is taken to be zero, because earth is a good
(a) insulator
(b) conductor
(c) semiconductor
(d) dielectric
Why must electrostatic field at the surface of a charged conductor be normal to the surface at every point ? Give reason.
The locus of all particles in a medium, vibrating in the same phase is called
(a) wavelet
(b) fringe
(c) wave front
(d) None of these
A double slit interference experiment is carried out in air and the entire arrangement is dipped in water. The fringe width
(a) increases
(b) decreases
(c) remains unchanged.
(d) fringe pattern disappears
Which of the following phenomenon is not explained by Huygen’s wave theory?
(a) Diffraction
(b) Polarisation
(c) Photoelectric effect
(d) Interference
Two wires of same length are shaped into a square and a circle. If they carry same current, the ratio of their magnetic moment-
a) 2:π
b)π:2
c) 4:π
d) π:4.
Twenty-seven drops of mercury are charged simultaneously to the same potential of 10 volts. What will be potential if all the charged drops are made to combine to form one large drop ?
(a) 180 V
(b) 90 V
(c) 120 V
(d) 45 V
Bending of Light phenomena is shown by
(a) Polarization
(b) Diffraction
(c) Interference
(d) Dispersion
In a meter bridge as shown, the balance point is found to be at 39.5 cam from the end A, when the resistor Y is of 12.5 Ω. Determine the balance point of the bridge above if X and Y are interchanged.
(a) 8.2 Ω, 40.6 cm
(b) 8.2 Ω, 60.4 cm
(c) 6.2 Ω, 60.4 cm
(d) 6.2 Ω, 39.6 cm