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The cause of being the refractive index (╬╝) of transparent medium > 1, is:
Speed of light in vacuum > speed of light in transparent medium
Speed of light in vacuum < speed of light in transparent medium
Wavelength of light gets change as it moves from denser to rarer medium
Speed of light in vacuum = speed of light in transparent medium
Speed of light in vacuum > speed of light in transparent medium
The refractive index (╬╝) of a transparent medium is defined as the ratio of the speed of light in vacuum (c) to the speed of light in that medium (v). Since light slows down when traveling through any material medium compared to a vacuum, c>v, which mathematically results in ╬╝>1.
The refractive index (╬╝) of a transparent medium is defined as the ratio of the speed of light in vacuum (c) to the speed of light in that medium (v). Since light slows down when traveling through any material medium compared to a vacuum, c>v, which mathematically results in ╬╝>1.
Think of light as a runner; running in a vacuum is like sprinting on a clear track, while passing through a medium is like running through water or a crowd, which naturally slows you down.
╬╝=vcтАЛ: C (Constant high) over V (Velocity slow).
╬╝=vcтАЛ тАФ definition of absolute refractive index, where c is the speed of light in vacuum and v is the speed in the medium.
╬╝>1 тАФ the condition resulting when c>v.
Refractive index quantifies how much light is bent or slowed upon entering a medium. Because a vacuum is the medium with the highest possible speed for light (cтЙИ3├Ч108┬аm/s), any other medium possessing atoms or molecules will interact with the electromagnetic wave, causing a reduction in its phase velocity (v). Thus, the ratio ╬╝=vcтАЛ will always yield a value greater than 1 for all common transparent materials.
The refractive index is a dimensionless quantity.
For vacuum, ╬╝=1 by definition.
For all other transparent media, ╬╝>1 because the speed of light is lower.
A higher refractive index indicates a denser optical medium.
Designing lenses for spectacles and microscopes.
Fiber optic communication systems.
Light always travels at its maximum possible speed in a vacuum.
Option B is incorrect because if the speed in the medium were higher, the refractive index would be less than 1, which contradicts physical laws.
Option C is incorrect because the wavelength of light changes in a medium, but the refractive index's fundamental definition is based on the change in velocity.
Option D is incorrect because this would imply the medium is a vacuum.
A is correct тАФ The refractive index ╬╝ is greater than 1 because the speed of light in vacuum (c) is always greater than the speed of light in a material medium (v).
Remember that light frequency remains constant when passing between media, but wavelength and speed change proportionally according to v=f╬╗.