Polaroid glasses is used in sun glasses because :
a. It reduces the light intensity to half on account of polarization
b. It is fashionable
c. It has good colour
d. It is cheaper
a. It reduces the light intensity to half on account of polarization
b. It is fashionable
c. It has good colour
d. It is cheaper
a. It reduces the light intensity to half on account of polarization
The interference phenomenon takes place
I. In all waves
II. In transverse waves only
III. In longitudinal waves only
IV. In standing waves only
The angle of incidence at which reflected light is totally polarised for reflection from air to glass (refractive index n) is
The wavefront due to a source situated at infinity is
(a) spherical
(b) cylindrical
(c) planar
(d) circular
The colours on the soap bubble is due to
(a) Interference
(b) Diffraction
(c) Polarisation
(d) Reflection
Which of the following is conserved when light waves interefere?
a. Energy
b.Phase
c. Intensity
d. Amplitude
The light sources used in Young’s double slit experiment are:
(A) Incoherent
(B) Coherent
(C) White light
(D) Blue-green-red Light.
Bending of Light phenomena is shown by
(a) Polarization
(b) Diffraction
(c) Interference
(d) Dispersion
A diffraction pattern is obtained by using a beam of red light. What will happen if the red light is replaced by the blue light.
a. No change will take place.
b. Bands become broader and farther apart.
c. Bands disappear
d. Diffraction bands become narrower and crowded.
Which of the following is not a property of electric field lines?
(A) Field lines are closed and continuous curves without any breaks.
(B) Two field lines cannot cross each other.
(C) Field lines start at positive charges and end at negative charges.
(D) They do not form closed loops.
The potential energy of a charged parallel plate capacitor is \(U_0\). If a slab of dielectric constant K is inserted between the plates, then new potential energy will be
(a) \(U_0\)/K
(b) \(U_0\)K²
(c) \(U_0\)/K²
(d) \(U_0\)²
A charge Q is enclosed by a Gaussian spherical surface of radius R. If the radius is doubled, then the outward electric flux will
(A) Increase four times
(B) be reduced to half
(C) remain the same
(D) Be doubled
A current carrying small loop behaves like a small magnet. If A be its area and M its magnetic moment, the current in the loop will be
a) M/A
b) A/M
c) MA
d) A²M
Select the correct statements from the following
(i) inside a charged or neutral conductor, electrostatic field is zero.
(ii) the electrostatic field at the surface of the charged conductor must be tangential to the surface at any point.
(iii) there is no net charge at any point inside the conductor.
(A) (i) and (ii)
(B) i) and (iii)
(C) (ii) and (iii)
(D) (i), (ii), and (iii)
Two capacitors of capacitance 6 µF and 4 µF are put in series across a 120 V battery. What is the potential difference across the 4 µF capacitor?
(a) 72 V
(b) 60 V
(c) 48 V
(d) zero