WorksheetsChapter 23 Wave Optics
Total questions: 12
Worksheet time: 21mins
In Young's two-slit experiment, a source of green light is used. The separation of fringes in the interference pattern produced can be increased by increasing
the distance between the screen and the slit
the size of every slit
the distance between the two slits
the intensity of the green light
The figure shows the diffraction pattern by a single slit which have a slit size of 0.017 mm and is placed 80 cm from the screen. The light used has a wavelength of 600 nm. What is the width of the central bright band?
5.65 cm
6.65 cm
7.21 cm
8.34 cm
A diffraction grating with 2400 lines per centimetre is used to produce a diffraction pattern that is recorded by a detector. The first-order fringe is 8.94 cm from central fringe. If the distance between the grating and the detector is 0.625 m, what is the wavelength of the electromagnetic wave used?
295 nm
590 nm
1180 nm
1190 nm
A diffraction grating that has 2000 slits per centimetre is used to measure the wavelengths emitted by hydrogen gas. At what angle in the first order spectrum would you expect to find the violet line that has a wavelength of 434 nm?
3°
5°
7°
9°
A plane polarized light is passed through a polaroid. The polarisation axis of the polaroid is adjusted until the intensity of the light passing through it is at maximum value
Imax . Through what angle must the polaroid be rotated so that the intensity of light that passes through it is 35% of Imax ?33.1°
42.6°
53.7°
64.8°
Two stars are just barely resolved by a telescope with a lens diameter of 0.500 m. Determine the angular separation of the two stars. Assume incident light of wavelength is 500 nm.
1.22×10−6 rad
2.44×10−6rad
3.66×10−6rad
4.88×10−6rad
The figure shows monochromatic light of wavelength, λ which is illuminated nearly normal onto a thin soap film of thickness, t and refractive index, n. The optical path difference between the reflected rays from the upper and lower surfaces of the soap film is
n2t
2nt
n2t+2λ
2nt+2λ
A beam of light which consists of two different wavelength λ1 and λ2 , ( λ1>λ2 ) is incident normally on a piece of diffraction grating. The second order line for λ1 and the third order line for λ2 overlap. What is the ratio of λ2λ1 ?
1.5
2.0
2.5
3.0
A binary star is observed with a telescope. A coloured filter is used to maximise the resolution. (A filter of a given colour transmits only that colour of light). What colour filter would give the greatest increase in the resolution?
Blue
Green
Yellow
Red
The Rayleigh criterion for resolving power for a circular aperture is
θ=1.22 Dλ . Two sources of radio waves are at a distance of 1 ×1012 m from the Earth. The sources are separated by 2 ×109 m and emit radio waves of wavelength 0.03 m. What is the estimate for the diameter of a dish of a radio telescope on the Earth that will just resolve the two sources?4×10−5m
4×10−4m
0.018 m
18 m
A beam of plane-polarised light is sent through two polarisers, the first at 60° to the original plane of polarisation and the second at 90° to the original plane of polarisation. What fraction of the original polarised intensity passes through the second polariser?
0
41
81
163
Light travelling along the core of an optical fibre, with a speed of 1.82 ×108 m s−1 meets the boundary with the cladding. The speed of light in the cladding is 1.89
4.0 °
8.0 °
37.2 °
74.4 °
