### MCQs of Waves Optics

Showing 1 to 10 out of 131 Questions
1.
In Young's experiment the distance between two slits is halved and the distance between the screen and slits is doubled. the width of the fringe _____ .
 (a) remains the same (b) becomes half (c) becomes double (d) becomes 4 times
2.
A diffraction is formed with red light. If red light is replaced by blue light, _____ .
 (a) the pattern does not change. (b) the maxima and minima are narrow and more crowded. (c) the maxima and minima are broadened and become distinct. (d) diffraction pattern disappears.
3.
To determine the position of a point like object precisely, _____ light should be used.
 (a) polarized (b) long wavelength (c) short wavelength (d) intense
4.
The angular spread of central maximum, in diffraction pattern , does not depend on _____
 (a) the distance between the slit and sources (b) wavelength of light (c) width of slit (d) frequency of light
5.
Detailed information can be obtained by the oil immersion objective of a microscope, because the objective has _____ .
 (a) large value of magnification (b) greater value of resolution (c) large diameter (d) none of above
6.

The distance between two slits in Young's experiment is 0.2 mm. If the wavelength of light used is 5000 Å, the angular position of 3rd bright fringe from the central bright fringe is _____ rad.

 (a) 0.075 (b) 0.75 (c) 0.0075 (d) 0.057
7.

In Young's experiment the distance between two slits is 0.4 cm and the distance of the screen from the slits is 100 cm. If the wavelength of light used is 5000 Å, the distance of 4th dark fringe from the central bright fringe is _____.

 (a) 4.37 × 10-2 cm (b) 4.37 mm (c) 8.74 × 10-2 cm (d) 8.74 mm
8.
The distance between two slits in Young's experiment is 0.1 mm and the distance of the screen from the slits is 100 cm. If the wavelength of light is 5000 Å the width of the fringe is _____.
 (a) 5 mm (b) 2.5 mm (c) 2.5 cm (d) 5 cm
9.
In Young's experiment if transparent thin sheets are placed in front of two thin slits such that the central bright fringe remain at the same position. Thickness and refractive index of both sheets are t1 and t2, and n1 and n2, respectively. In this case, _____
 (a) (b) (c) (d)
10.
A plate of refractive index 1.5 is placed in the passage of one ray in Young's experiment. if the central fringe is bright, the minimum thickness of the plate is _____ .
 (a) (b) $\lambda$ (c) $\frac{\lambda }{3}$ (d) $\frac{2\lambda }{3}$
Showing 1 to 10 out of 131 Questions