Physics · Science General

Optics and Light Properties

2,019 Questions

Optics and light properties focus on the behavior of light, including reflection, refraction, dispersion, and polarization. This topic also covers the wave nature of light, illumination, and the functioning of optical instruments like microscopes. Questions on these concepts are common in general science sections of SSC, Railways, and State exams.

Reflection and mirrorsRefraction and mediumsLight wave theoriesPolarization and intensity

Optics and Light Properties Questions

Multiple choice

Twinkling of stars is due to

  1. atmospheric refraction of starlight

  2. atmospheric dispersion of starlight

  3. atmospheric reflection of starlight

  4. atmospheric refraction of sunlight
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The twinkling of stars is caused by the atmospheric refraction of starlight, where the light passes through layers of air with varying densities and temperatures, causing the path of light to bend.

Multiple choice

Why does yellow colour appear yellow to our eyes?

  1. Due to reflection of yellow colour

  2. Due to absorption of yellow colour

  3. Due to scattering of yellow colour

  4. Due to refraction of yellow colour
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The colour depends on surface and texture of an object or how it bends light. Light in its natural state is white light. In case of yellow colour, the yellow object reflects yellow colour and absorbs all the other colours. So, it appears as yellow.

Multiple choice

A mirage is observed in deserts due to the phenomenon of

  1. interference of light

  2. total internal reflection

  3. scattering of light

  4. double refraction of light
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A mirage is observed in deserts due to the phenomenon of total internal reflection. As we move up from the surface  the temperature  of the layers of the air   decreases because of  which the refractive index of the air increases hence total internal reflection takes place.

Multiple choice

What are three types of lasers?

  1. Gas, solid state, diode

  2. Diode, inverted, pointer

  3. Pointer, diode, CD

  4. Gas, metal vapor, rock
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Lasers are categorized by their gain medium, which includes gas lasers (like CO2), solid-state lasers (like Nd:YAG), and semiconductor (diode) lasers.

Multiple choice

Which of the following techniques is a gradual bending of the rays due to the change in effective dielectric constant of the atmosphere through which the wave is passing?

  1. Diffraction loss

  2. Operation subsystem

  3. Tropospheric refraction

  4. Tropospheric reflection

  5. Cell
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This technique is a general bending of the rays due to the change in effective dielectric constant of the atmosphere through which the wave is passing.

Multiple choice

What are three major types of lasers?

  1. Gas, solid state, diode

  2. Diode, inverted, pointer

  3. Pointer, diode, CD

  4. Gas, metal vapor, rock
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The three major types of lasers are gas lasers (like HeNe), solid-state lasers (like Ruby or Nd:YAG), and semiconductor/diode lasers.

Multiple choice

Which device is used to project an opaque object?

  1. Slide projector

  2. Magic lamp

  3. Film strip projector

  4. Epidiascope
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An epidiascope is an optical device capable of projecting both transparent (slides) and opaque objects (like pages of a book or photos) onto a screen.

Multiple choice

A pond appears less deep due to

  1. reflection

  2. diffraction

  3. refraction

  4. polarisation

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Refraction is the bending of light as it passes from one medium to another, such as from water to air. This change in direction causes objects submerged in water to appear at a shallower depth than they actually are.

Multiple choice

When light wave travel's from air to glass, which variables are affected?

  1. wavelength , frequency and velocity

  2. velocity and frequency only

  3. wavelength and frequency only

  4. wavelength and velocity only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When light travels from air to glass, its velocity decreases and its wavelength decreases. However, the frequency of the light wave remains constant because it is determined by the source.

Multiple choice

Directions: A part of the sentence or the entire sentence is underlined, followed by four ways of phrasing it. Choose the alternative which is grammatically correct and concise.

When it shines through a prism, a beam of white light broke into all colors of the rainbow.

  1. When it shines through a prism, a beam of white light broke into all colors of the rainbow.

  2. When shined through a prism, a beam of white light broke into all colors of the rainbow.

  3. When shone through a prism, a beam of white light breaks into all colors of the rainbow.

  4. When shone through a prism, a beam of white light breaks in all colors of the rainbow.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Case of present indefinite tense. Option 1 & 2 are grammaticaslly incorrect. There is prepositional error (preposition 'in') in the 4rth sentence. Hence, option 3.

Multiple choice

Non-luminous objects are visible because they ______________________.

  1. reflect light into our eyes

  2. pass light through them

  3. reflect light in one direction

  4. do not reflect light

  5. -
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct answer. When light falls on non-luminious objects some amount of light is reflected back in our direction, as a result we can see the object.

Multiple choice

What is meant by 'rectilinear propagation of light'?

  1. Light travels in a curved line.

  2. Light can bend around the corners.

  3. Light travels in a straight line.

  4. Light passes through opaque objects.

  5. -
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the correct answer. Light does travel in straight line as it casts shadow of opaque object which falls in its path.