HARD
Earn 100

State and explain Rayleigh's criterion.

Important Questions on Wave Optics

EASY
Assume that the light of wavelength is 6000A coming from a star. What is the resolution limit of a telescope whose objective has a diameter of 100 inch?
MEDIUM
The aperture diameter of a telescope is 5 m . The separation between the moon and the earth is 4×105 km . With light of wavelength of 5893 Å , the minimum separation between objects on the surface of moon, so that they are just resolved, is close to:
EASY
Two poles are separated by a distance of 3.14 m The resolving power of human eye is 1minute of an arc. The maximum distance from which he can identify the two poles distinctly is
EASY
If the wavelength of light used is 6000 Å. The angular resolution of the telescope of an objective lens having diameter 10 cm is _____ rad.
HARD
Two stars are 10 light years away from the earth. They are seen through a telescope of objective diameter 30 cm. The wavelength of light is 600nm. To see the stars just resolved by the telescope, the minimum distance between them should be 1 light year=9.46×1015m of the order of :
EASY
The speed of electrons in a scanning electron microscope is 1×107 ms-1. If the protons having the same speed are used instead of electrons, then the resolving power of scanning proton microscope will be changed by a factor of:
MEDIUM
Assume that light of wavelength 600 nm is coming from a star. The limit of resolution of telescope whose objective has a diameter of 2 m is:
MEDIUM
Larger aperture of objective lens in an astronomical telescope _____
EASY
Calculate the limit of resolution of a telescope objective having a diameter of 200 cm , if it has to detect light of wavelength 500 nm coming from a star.
EASY
Diameter of the objective lens of a telescope is 250 cm. For light of wavelength 600 nm coming from a distant object, the limit of resolution of the telescope is close to:
EASY
On decreasing the wavelength of incident light from 8000 A to 4000 A, the intensity of the scattered light in Rayleigh scattering will become how many times the initial scattered intensity?
EASY
The ratio of resolving powers of an optical microscope for two wavelengths λ1=4000  and λ2=6000 Å is
EASY
A telescope has an objective lens of 10 cm diameter and is situated at a distance 1 km from two objects. The minimum distance between these two objects which can be resolved by the telescope, when the mean wavelength of the light is 5000 Ao, is of the order of
EASY

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : An electron microscope can achieve better resolving power than an optical microscope.

Reason R : The de Broglie's wavelength of the electrons emitted from an electron gun is much less than wavelength of visible light.

In the light of the above statements, choose the correct answer from the options given below:

HARD
An LED display consists of 100 pixels per cm2. Consider that the diameter of the pupil of the eye is 5 mm and the average wavelength of the display is 575 nm. What is the nearest distance from the display one can be at, such that the display does not appear pixelated?
EASY
A microscope was initially placed in air (refractive index 1). It is then immersed in oil (refractive index 2). For a light whose wavelength in air is $\lambda$, calculate the change of microscope's resolving power due to oil and choose the correct option
MEDIUM
The aperture of the objective is 24.4 cm. The resolving power of this telescope, if a light of wavelength 2440 A is used to see the object will be
EASY
The value of numerical aperture of the objective lens of a microscope is 1.25. If light of wavelength 5000 A is used, the minimum separation between two points, to be seen as distinct, will be:
EASY
The diameter of the objective lens of the microscope makes an angle β at the focus of the microscope. Further, the medium between the object and the lens is the oil of the refractive index n. Then the resolving power of the microscope.
HARD
Assuming that the human pupil has a radius of 0.25 cm and a comfortable viewing distance of 25 cm. The minimum separation between two point objects that the human eye can resolve for the light of wavelength 500 nm is