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

The variation if focal length of a lens when we pass from the central portion out words (to words the lens edges) is known as

• Astigmatism A
• Chromatic B
• Spherical aberration C
• Coma D

The resolution of microscope depends on objective's

• Focal length A
• Material B
• Diameter C
• None of these D

Fraunhofer spectrum is a

• Line absorption spectrum A
• Band absorption spectrum B
• Line emission spectrum C
• Band emission spectrum D

• 
  A
• 
  B
• 
  C
• 
  D

In young s interference experiment one slit is covered with a cellophane paper which absorbs half the intensity then

• No fringes are observed A
• All fringes will be darks B
• bright fringes will be less bright and dark will be less dark C
• Bright fringes will be brighter and dark fringes will be darks D

Light waves are:

• Transverse waves A
• Longitudinal waves B
• Compressional waves C
• None of them D

Experimental demonstration of wave nature of light was given in 1801 by

• New ton A
• Maxwell B
• Thomas young C
• Huygen D

In spectrometer the function of collimator is to produce

• Diverging beam of light A
• Converging beam of light B
• Parallel beam of light C
• None of these D

Television signal are converted into light signals by

• Decoder A
• Transistor B
• Photodiode C
• Optical fibre D

A thin layer of oil on the surface of water looks colored due to:

• Diffraction of light A
• Reflection of light B
• Dispersion of light C
• Interference effect of light D

Which does not show polarization

• Longitudinal wave in gas A
• Transverse wave in gas B
• Both a and b C
• None of these D

An optical fibre with its protective case may be typically 6.0 mm in diameter and yet it can replace bundle of copper of diameter

• 6.79 cm A
• 6.95 cm B
• 7.52 cm C
• 7.62 cm D

The wavefront formed at very large distance from the source is:

• Cylindrical A
• Spherical B
• Elliptical C
• Plane D

When 'θ' is small then

• tan θ ≈ sin θ A
• cos θ ≈ sin θ B
• sin θ ≈ tan θ C
• None of these D

The wavelength of refractive wave in a denser medium is

• Same as that of the incident wave A
• Become smaller than the incident B
• Becomes greater than the incident wave C
• None of these D

Sunset makes sky appears reddish because of:

• Diffraction of sun rays A
• Refraction of light B
• Scattering of light from dust particles C
• Polarization of ligth D

In young's slit experiment on interference the ratio of the intensities of a bright band and a dark band is 6 : 1 the ratio of the amplitudes o the interfering waves is

• 16 A
• 5/3 B
• 4 C
• 1/4 D

How are X-rays diffracted by crystals in X-rays crystallography?

• they bounce off the nucleus A
• they are diffracted whey they pass from between them acting as a slit B
• they are diffracted by the electron clouds in the atoms C
• they hit the side the nucleus and change direction and thus are diffracted D

Which one of the following can act approximately as a source of monochromatic light

• Neon lamp A
• Fluorescent tube B
• Sodium lamp C
• none of these D

When light travels from one medium to another which are separated by a sharp boundary the characteristic which does not change is

• Velocity A
• Wavelength B
• Frequency C
• Amplitude D