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

LASER is an acronym for:

  1. Light Amplification Stimulation Emission of Radiation

  2. Light Advancement with Structured Radar
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

LASER is an acronym for Light Amplification by Stimulated Emission of Radiation. Option A is the standard definition.

Multiple choice physics measurements and units measuring mass measurement of mass measuring instruments

Objects measured in beam balance should be

  1. hot and wet

  2. hot but not wet

  3. wet but not hot

  4. neither hot nor wet
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

While weighting an object using a beam balance, it should be ensured that the object is neither wet nor hot.
Meanwhile, let us look at all the precautions in using a beam balance: 
1. The weight should be replaced into the weight box after weighing. 
2. Wet and hot objects should not be kept on the plan. 
3. When near the actual weight ,weights should be tried in decreasing order. 
4. The beam should be lowered before adding or removing weights from the pan. 
5. The lever should be turned gently ,in order to prevent the knife edges from chipping.

Multiple choice botany metabolism, cell respiration, and photosynthesis light dependent or hill reaction phases of photosynthesis emerson's experiments & hill's reaction

The phenomenon of re-irradiation of absorbed light is called

  1. Photoluminescence

  2. Chemiluminescence

  3. Phosphorescence

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

Photoluminescence is the phenomenon of light emission after absorption of photons in the form of electromagnetic radiation. Chemiluminescence is the phenomenon of emission of light from a chemical reaction. Phosphorescence is a type of photoluminescence which is related to fluorescence. It does not re-irradiate the absorbed light immediately like fluorescence. Fluorescence is the phenomenon of re-irradiation of light absorbed light or electromagnetic radiation.

Thus, the correct answer is option D.

Multiple choice

Why can’t you see in the dark?

  1. There is not enough light for reflection into the human eye

  2. We can see in the dark using night vision!

  3. We momentarily turn blind in the dark.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Vision requires light to reflect off objects and enter the eye. In the absence of light, there is no reflection, so we cannot see.

Multiple choice physics wave optics resolving power of optical instruments resolution of optical instruments diffraction

 A beam of plane polarised light falls on a polarizer which rotates about axis of ray with angular velocity $\omega $. The energy passing through polrizer in one revolution if incident power is P is :

  1. $ \dfrac {\pi P} {2\omega} $
  2. $ \dfrac {\pi P} {\omega} $
  3. $ \dfrac {2 \pi P} {\omega} $
  4. $ \dfrac {3 \pi P} {2\omega} $
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice chemistry metals chemical properties and uses of metals and non-metals introduction to metals physical properties of non-metals

The glass bulb of electric bulbs becomes black due to the deposition of vapour from the:

  1. glass of the bulb

  2. metal filament

  3. gas in the bulb

  4. joint in the glass
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Over the life of an incandescent light bulb, the filament begins to deteriorate and the particles will settle on the inside of the glass. In return the bulb will take on a grayish appearance and a slight decrease in light output may occur.
  • For fluorescent bulbs only, the ends will blacken as the bulb is burned. Each time the lamp is turned on and off the emissions material settles on the inside of the glass. Extreme darkening generally indicates the bulb is about to burn out.
Multiple choice polarisation of light polarisation wave optics optics physics

In case of linearly polarised light, the magnitude of the electric field vector.

  1. Does not change with time

  2. Varies periodically with time

  3. Increases and decreases linearly with time

  4. Is parallel to the direction of propagation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In any type of light whether polarised or unpolarised, the magnitude of electric field vector always varies periodically with time.
Actually the change in electric field vector gives rise to periodically changing magnetic field.