The phenomenon of diffraction can be treated as interference phenomenon if the number of coherent sources is:
(A) one
(B) two
(C) zero
(D) infinity
(A) one
(B) two
(C) zero
(D) infinity
(D) infinity
In the Young double slit experiment, the fringe pattern as seen on the screen is:
(A) Parabola
(B) Hyperbola
(C) Ellipse
(D) Spiral
A phase difference of 5π corresponds to a path difference (in terms of λ) of:
(a) 5λ
(b) 10λ.
(c) 5λ/2
(d) 2λ
The idea of secondary wavelets for the propagation of a wave was first given by
(a) Newton
(b) Huygens
(c) Maxwell
(d) Fresnel
The colours on the soap bubble is due to
(a) Interference
(b) Diffraction
(c) Polarisation
(d) Reflection
The wave-front due to source situated at the infinity is
(A) Spherical
(B) Cylindrical
(C) Plane
(D) Rectangular
The parameter of light wave which remain same after refraction
(A) speed
(B) frequency
(C) wavelength
(D) none of these
When light suffers reflection at the interface between water and glass, the change of phase in the reflected wave is
(a) zero..
(b) π.
(c) π/2.
(d) 2π.
When a polaroid is rotated, the intensity of light varies but never reduces to zero. It shows that theincident light is:
a. Unpolarised
b. completely plane polarised
c. partially plane polarised
d. one of the above
When a compact disc is illuminated by a source of white light , colored lines are observed. This is due to
I. Interference
II. Diffraction
III. Dispersion
IV. Refraction
The capacitance of earth, viewed as a spherical conductor of radius 6408 km is:
(a) 1420 μF
(b) 712 μF
(c) 680 μF
(d) 540 μF
For any charge configuration equipotential surface through a point is normal to the electric field.
1. Since W=Fscosθ is zero so field is normal to the surface
2. As W≠0
3. Work done can be Zero if Field is parallel to the field
4. None of these
In Young’s double slit experiment the distance between the slit and the screen is doubled and the separation between the slit is reduced to half. The fringe width:
(a) is doubled
(b) become four time
(c) is halved
(d) remain unchanged
Let \(ε_0\) denote the dimensional formula of the permittivity of vacuum. If M=mass, L=length, T=time and
I=electric current, then
(A) [M⁻¹L⁻³T²I]
(B) [M⁻¹L⁻³T⁴I²]
(C) [M⁻¹L²T⁻¹I⁻²]
(D) [M⁻¹L²T⁻¹I]
Three capacitors 3 μF, 6 μF and 6 μF are connected in series to a source of 120 volt. The potential difference across the 3 μF capacitor will be
(a) 40 volt
(b) 30 volt
(c) 40 volt
(d) 60 volt