MDCAT Physics Chapter 7 MCQ Test With Answer for (Light )

If the focal of a convex lens is 5 cm then to get real and inverted image of the same size as that of object, the object should be placed at

• 5 cm A
• 10 cm B
• 15 cm C
• 20 cm D

A fiber of 50μm diameter capable of carrying white light at ______ distances is called ______ index fiber

• Large, multi-mode step A
• Small, multi-mode step B
• Small, multi-mode graded C
• Large, single mode step D

In Newton's rings the thickness of air film at the point of contact is

• maximum A
• minimum B
• equal to wavelength C
• zero D

In viewing the distant objects the angle subtended at the telescope is

• Smaller A
• Bigger B
• Very large C
• None of these D

The light produced by a laser is all the following except

• Incoherent A
• Monochromatic B
• In the form of a narrow beam C
• Electromagnetic D

According to the Huygen's principle, the secondary wavelets propagate in the forward direction with a speed equal to

• speed of wave motion A
• speed of medium B
• speed of electrons C
• speed of protons D

In an optical fibre the speed of light is

• Directly proportional to its refractive A
• Inversely proportional to its refractive inedex B
• Independent of refractive index C
• Directly proportional to square of refractive index D

If a light of λ = 588 nm falls on half silvered glass plate in Michelson s interferometer if movable mirror is moved through 0.233 mm the number of fringes will be observed to shift

• 795 A
• 792 B
• 786 C
• None D

Critical angle of light passing from glass to air is minimum for

• Red A
• Green B
• Yellow C
• Violet D

• 
  A
• 
  B
• 
  C
• 
  D

A convex lens is dipped in a liquid whose refractive index is equal to the material of the lens. Then its focal length will become

• Infinite A
• Zero B
• Extremely small C
• Extremely large D

Who proposed that light energy form a luminous source travels in space by means of wave motion?

• Newton A
• Maxwell B
• Einstein C
• Huygen D

Maximum detail of object can be seen from a microscope wen light used is of

• Shorter wavelength A
• Longer wavelength B
• White light C
• Any light D

Newton's rings are:

• Rectangular A
• Spherical B
• Concentric circles C
• None of these D

In an interference pattern of Ypung's double Slit (YDS) experiment:

• Bright fringes are wider than dark fringes A
• Dark fringes are wider than bright fringes B
• Both dark and bright fringes are of equal width C
• Central fringes are wider than the outer fringes D

For destructive interference the path difference is give by:

• (m-1/2)λ A
• (m+1/2)λ B
• mλ C
• 1/2 mλ D

The light signal in graded index fibre is totally confined due to

• Total inernal reflection A
• Continuous refraction B
• Both a and b C
• Dispersion D

The least distance of he distinct vision is

• 20 cm A
• 22 cm B
• 25 cm C
• 30 cm D

How is the interference pattern in Young's double slit experiment affected if the sodium light is replaced by red light of the same intensity

• The fringes will vanish A
• The fringes will become brighter B
• The fringes will increase C
• The fringes will decrease D

The central point in the Newton's rings is dark due to

• Destructive interference A
• Constructive interference B
• Additional of path difference λ/2 C
• b and c D