Tag: physics

Questions Related to physics

The splitting of white light into several colours on passing through a glass prism is due to -

  1. Refraction

  2. Reflection

  3. Interference

  4. None of these


Correct Option: A
Explanation:

The splitting of white light into its constituent colour is called dispersion. Dispersion occurs because refraction or bending differs with the colour.

What does the dispersion of light in a medium imply
i) Lights of different wavelength travel with different speeds in the medium.
ii) Light of any frequency will travel with the same speed in the medium
iii) The refractive index of the medium is different for different wavelength of light

  1. $(i)$ and $(ii)$ only

  2. $(ii)$ and $(iii)$ only

  3. $(i)$ and $(iii)$ only

  4. $(i),(ii)$ and $(iii)$


Correct Option: C

The colour are characterised by which of following character of light.

  1. Frequency

  2. Amplitude

  3. Wavelength

  4. Velocity


Correct Option: C
Explanation:

White light is incident combination of various colours each having different wavelengths. 

Thus colour is characterised by wavelength of light. 

The deflection of light by minute particles and molecules in all distraction is known as ____of light .

  1. dispersion

  2. interference

  3. diffraction

  4. scattering


Correct Option: A

When the white light is passed through a equilateral prism it splits into seven colours. The phenomena of splitting of white light is called :

  1. $refraction$

  2. $spectrum$

  3. $dispersion$

  4. $scattering$


Correct Option: C

The phenomenon due to which white light splits into seven colours on passing through a prism is called _________

  1. reflection

  2. refraction

  3. dispersion

  4. all the above


Correct Option: C
Explanation:

The phenomenon due to which white light splits into seven colours on passing through a prism is called dispersionWhite light is made up of seven bands of colors each having different wavelengths. Upon passing through a medium, each of the colors travels at different speeds and hence has different angles of refraction leading to the splitting of the light i.e. dispersion.

A rainbow is formed when the air is completely dry

  1. True

  2. False


Correct Option: B
Explanation:

False. It is formed only after or before the rains when the air is full of moisture

A ray of light after passing through a medium were spread up into different colours. The phenomenon is called :

  1. Total internal reflection

  2. Diffraction

  3. Dispersion

  4. Deviation


Correct Option: C
Explanation:

A ray of light after passing through a medium were spread up into different colours. The phenomenon is called dispersion.

Dispersion of white light into its constituent colours occurs during :

  1. Reflection at a plane mirror

  2. Reflection at a concave mirror

  3. Internal reflection inside a spherical drop of water

  4. Refraction at the boundary of a transparent medium


Correct Option: D
Explanation:

Answer is D.

The spectral colors of the rainbow are caused by dispersive refraction. Newton established that refraction causes the dispersion of light into its constituent colours. He named seven colors, in symmetry with the seven distinct notes in the Western musical scale.
Refraction is the bending of a light as it crosses the boundary into a different medium and it is determined by its refractive index, or how much the light is slowed down in the new medium.
Hence, dispersion of white light into its constituent colors occurs during refraction at the boundary of a transparent medium.

The splitting of white light into several colours on passing through a glass prism is due to

  1. refraction

  2. reflection

  3. dispersion

  4. none of these


Correct Option: C
Explanation:
$ \bf{Refraction} $ of light is the phenomenon of bending of light or change in the direction of light, when it passes obliquely from one transparent medium to another.

$ \bf{Reflection} $ is the phenomenon in which light rays on striking a polished surface(such as a mirror) bounce back or are sent back into the same medium. 

$\bf{Dispersion} $ is the phenomenon of splitting of white light into its component colours (VIBGYOR) on passing through a glass prism.


Hence, the correct answer is OPTION C.