Physics · Science General

Optics and Light Properties

2,013 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

What is Optics?

  1. Study of heat

  2. Study of the properties of light

  3. Study of spectacles

  4. Study of colours

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

Optics is the branch of physics that studies the properties and behavior of light, including its interactions with matter and the construction of instruments that use or detect it. While spectacles and colors are related to optics, they are applications rather than the definition itself. Heat is studied in thermodynamics.

Multiple choice

The visibility in a TAF is denoted in

  1. SM

  2. NM

  3. KM

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

TAF (Terminal Aerodrome Forecast) reports visibility in statute miles (SM) in the United States. This is standard aviation weather reporting format.

Multiple choice

On which of the following principles does optical fibre work?

  1. Refraction

  2. Scattering

  3. Interference

  4. Total Internal reflection
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total Internal Reflection is correct. Optical fibers work on the principle of Total Internal Reflection (TIR). Light signals travel through the core (higher refractive index) and when they strike the core-cladding boundary at an angle greater than the critical angle, they are completely reflected back into the core. This allows light to travel long distances with minimal loss. Refraction would cause light to escape, scattering causes loss, and interference is not the principle.

Multiple choice

Which of the following results in the red colour of the rising and the setting sun, and the blue colour of the sky?

  1. The insolation received by the surface of the Earth

  2. The absorption of light within the atmosphere

  3. The scattering of light within the atmosphere

  4. The absorption of long wave solar radiation within the troposphere

  5. The transfer of shortwave solar radiation through the air waves
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The red colour of the rising and the setting sun, and the blue colour of the sky are the result of scattering of light within the atmosphere. This is the correct answer choice.

Multiple choice

What are luminous objects?

  1. objects which allow light to pass

  2. objects which emit light

  3. objects which do not allow light to pass

  4. objects which do not emit light
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The object which emit or give out their own light are called luminous object e.g. Sun, Stars, torch, electric bulb, tube light etc.

Multiple choice

What are opaque object?

  1. objects which do not allow light to pass

  2. objects that allow light to pass partially

  3. object that reflect light

  4. object that are conductive
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The object do not allow light to pass through them are called opaque objects and nothing can be see through these objects Eg. Table, chair, book, iron (or any metal)

Multiple choice

Light can traveled through________.

  1. air

  2. soil

  3. rocks

  4. wood
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Air is a transparent mixture of gases which allow light to pass through it whereas soil, rock and wood are the examples of opaque object i.e. they do not allow light to travel through them at all.

Multiple choice

The objects which allow light to pass partially are called ______.

  1. non-luminous

  2. opaque

  3. transparent

  4. translucent
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Transparent objects
Allow light to pass through clearly able to see thought
Water, air glass , cellophane, plastic sheet
Translucent
Allow light to partially pass through which one can not see clearly
Prosted glass, plastic ruler, butter paper
Opaque
Do not allow light to pass through cannot see through the object
Table, chair, book, iron (or any metal)

So the objects which allow light to pass partially are called translucent objects.

Multiple choice

Why empty cardboard cartons act as a dark room?

  1. as it allow light to pass

  2. as it do no allow light to pass

  3. as it reflects the light

  4. as it emits light
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Whenever an opaque object is kept in the path of the light it forms and dark patch behind itself. This dark patch is known as shadow. It is always black in colour irrespective of the object colour or light colour falling on it. As empty cardboard cartons are opaque so they do not allow light to pass through then and always etc as dark room.

Multiple choice

Which one of the following is a feature of shadow?

  1. a shadow is of same colour of that of object

  2. a shadow is formed by an opaque object

  3. a shadow is of same size of that of object

  4. a shadow is formed due to reflection of light
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Shadow is always formed by an opaque object. Shape of the shadow depends upon 2 factors:

  1.         size of source of light
  2.         position of source of light. Smaller the size of light source, larger will be the image, formed and greater is the distance between the object and light source, light will be the image formed. A shadow is always black is colour and is different in size than that of the object.
Multiple choice

_______ and ________ are required to see a shadow.

  1. Darkness and a transparent object

  2. Source of light and an opaque object

  3. An opaque object and darkness

  4. A non – luminous object and darkness
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Whenever an opaque object is kept in the path of the light, it forms a dark patch behind itself. This dark patch is known as a shadow. It is always black in colour irrespective of the object colour or light colour falling on it. So, it is an opaque object and a source of light, required to see the shadow.

Multiple choice

Glass, cellophane and plastic sheet are examples of __________ objects.

  1. transparent

  2. opaque

  3. translucent

  4. luminous
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Transparent objects
Allow light to pass through and we can clearly able to see through them
Water, air, glass, cellophane, plastic sheet
Translucent objects
Allow light to partially pass through and we cannot see through them clearly
Frosted glass, plastic ruler, butter paper
Opaque objects
Do not allow light to pass through and we cannot see through them
Table, chair, book, iron (or any metal)

 

Multiple choice

When sunlight falls on a soap bubble bright colours are seen. They are produced by:

  1. dispersion

  2. interference

  3. refraction

  4. pigments in the soap

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

The colorful patterns on soap bubbles are caused by thin film interference. When white light strikes the thin soap film, some waves reflect from the outer surface while others penetrate and reflect from the inner surface. These reflected waves interfere constructively or destructively depending on film thickness, creating colors. Dispersion splits light into colors in prisms, refraction bends light, and soap has no pigments.