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

Rainbow an arch in the sky usually seen after rain is the result of

  1. reflection and refraction

  2. refraction of light only

  3. reflection of light only

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

Rainbows are formed by dispersion, refraction, and internal reflection of sunlight within water droplets. White light disperses into colors, reflects off the back of the droplet, and refracts again as it exits. This requires multiple optical processes working together.

Multiple choice

Medium through which light cannot pass is called

  1. transparent

  2. opaque

  3. translucent

  4. alloy
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An opaque medium is one through which light cannot pass - it either absorbs or reflects all light. Transparent materials allow light to pass through clearly, while translucent materials allow partial passage. Option B (opaque) is correct.

Multiple choice

Which of the following statements is/are true? a. Objects can be classified on the basis of properties of the materials that they are made from. b. Object made from transparent material allows to easily see through it.
c. Objects through which one cannot see at all are called translucent materials.

  1. Only a

  2. Only b

  3. Only c

  4. Only a and b

  5. Only b and c
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Both these statements are correct. Thus, this is the correct answer.

Multiple choice

Danger signals are generally red as red light

  1. Is least bright

  2. Undergoes least deviation

  3. Has lowest velocity

  4. Gives comfort to eye
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Red light is used for danger signals because it undergoes the least deviation (scattering) when passing through atmospheric particles like dust, fog, and water droplets. According to Rayleigh scattering, longer wavelengths (red) scatter less than shorter wavelengths. This makes red light most visible over long distances and in poor visibility conditions.

Multiple choice

Night photography and photography in mist and fog are possible using

  1. gamma radiation

  2. ultra violet radiation

  3. infrared radiation

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

Infrared radiation has longer wavelengths than visible light and can penetrate haze, fog, and darkness better. This makes it ideal for night photography and shooting through mist. Gamma and UV radiation don't have this property for photography.

Multiple choice

……….waves cannot be transmitted through vacuum.

  1. Light

  2. Heat

  3. Sound

  4. Electromagnetic
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sound waves are mechanical waves that require a material medium (solid, liquid, or gas) to propagate. They cannot travel through vacuum because there are no particles to compress and rarefy. Light and electromagnetic waves can travel through vacuum as they are self-propagating oscillating fields.

Multiple choice

Stars twinkle because of -------- of light.

  1. reflection

  2. scattering

  3. emission

  4. absorption
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Stars appear to twinkle because of atmospheric scattering and refraction of light as it passes through moving air layers of varying density. This continuous shifting causes the star's apparent position and brightness to fluctuate rapidly from Earth's perspective.

Multiple choice

If the refraction index decreases with height over a portion of the range of height, the rays will be curved downwards. Here, which of the following conditions can occur?

  1. Trapping of duct propagation

  2. Low power low antenna approach

  3. Tropospheric refraction

  4. Power consumption

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

If the refraction index decreases with height over portion of the range of height, the rays will be curved downwards and then trapping of duct propagation can occur.