Which of the following optical properties of light enables sunglasses to reduce glare from sunlight reflected off surfaces such as water or roads?
Polarization
Ordinary sunlight is unpolarised, meaning its electric field vibrates in all directions perpendicular to the direction of travel.
When light reflects off a horizontal non-metallic surface such as water or a road, the reflected light becomes largely horizontally polarised. This concentrated horizontally-vibrating light is what we perceive as harsh glare.
Polaroid (polarising) sunglasses contain a filter whose transmission axis is oriented vertically. This axis blocks the horizontally polarised glare while allowing useful vertically polarised light to pass, so the glare is greatly reduced.
The other options cannot do this: refraction is the mere bending of light, diffraction is the spreading of light around obstacles, and interference is the superposition of waves; none of them selectively removes light vibrating in one particular plane.
Hence, the property that enables sunglasses to cut reflected glare is Polarization.
Similar Questions
- The ability of a medium to refract light is also expressed in terms of its:
- The center of the reflecting surface of a spherical mirror is a point called:
- The lens which is thin in the middle and thick at its periphery is called a:
- Which colour deviates the least when light passes through a prism?
- Shadows are formed when _____ objects come in the path of light.
- If a lens has a focal length of $25\text{ cm}$, what will be the power of that lens?
- Which kind of mirrors is used as rear view wing mirrors in vehicles?
- For a person with Hypermetropia or far-sightedness, the near point, is _____ farther away from the normal near point.
- Light travels in a:
- Which type of mirror is used by dentists to see large images of patients' teeth?
Important Questions from Optics
Which one of the following colours may be obtained by combining green and red colours?
Which of the following are the primary colours of light?
Directions: The following items consist of two statements, Statement I and Statement II. You are to examine these two statements carefully and select the answers to these items using the code given below:
Statement I: Diamond is very bright.
Statement II: Diamond has very low refractive index
A non-SI unit called 'nit' is the unit of which of the following photometric quantities used to measure a multitude of light intensity?
Which among the following is used as a reflector in search lights?
