A slit of width a is illuminated by white light. The first minimum for red light will fall at 30o, when a is
3250 Å
6.5 × 10-4 mm
1.3 micron
2.6 x 10-4 mm
Two sodium lamps are used in an interference experiment. The intensity produced by both lamps individually on the screen is I. The ratio of intensity of maxima to intensity of minima on the screen is
2:1
1:2
∞:1
1:1
Two points separated by a distance of 0.1 mm can just be inspected in a microscope when light of wavelength 6000 Å is used. If the light of wavelength 4800 Å is used, this limit of resolution will become
0.80 mm
0.12 mm
0.10 mm
0.08 mm
Light of wavelength 6328 is incident on a slit having a width 0.2 mm. The width of the central maximum, measured from minimum to minimum is:
0.36 degrees
0.18 degrees
0.72 degrees
0.09 degrees
The Young's double slit experiment is performed with blue and with green light of wavelengths 4360 Å and 5460 Å respectively. If x is the distance of the 4th maxima from the central one, then
x(blue) = x(green)
x(blue) > x(green)
x(blue) < x(green)
x(blue) / x(green) = 5460/4360
Which of the following phenomenon is not common to sound and light waves?
interference
diffraction
coherence
polarisation
In Young's double slit experiment, let S1 and S2 be the two slits, and C be the centre of the screen. If∠S1CS2 = θ and λ is the wavelength, the fringe width will be
λ/θ
λ θ
A beam of ordinary unpolarised light passes through a tourmaline crystal C1 and then it passes through another tourmaline crystal C2 which is oriented such that its principle plane is parallel to that of C2. The intensity of emergent light is I0. Now, C2 is rotated by 60o about the ray. The emergent ray will have an intensity
2 I0
I0 / 2
I0 / 4
I0 / √2
The resolution limit of the eye is 1. At a distance of x km from the eye, two persons stand with a lateral separation of 3 metres. For the two persons to be just resolved by the naked eye, x should be
10 km
15 km
20 km
30 km
In Young's double slit experiment using red and blue lights of wavelengths 600 nm and 480 nm respectively, the value of n for which the nth red fringe coincides with (n + 1)th blue fringe is
5
4
3
2