Question

The dimensionless variable among the following is
1)Planck's constant
2)Speed of Light
3)Force
4)Refractive Index​

Answer 1

Answer:

4) Refractive Index

Explanation:

It is the ratio of the speed of lights in different mediums so $\\\tt ms^{-1}$ cancel out.

• Plank's constant is gained by relation $\\\tt E= h \nu$ which clearly doesn't makes h dimensionless since v has unit of  $\\\tt T^{-1}$ and E has units of energy.
• Speed of light has units of $\\\tt ms^{-1}$.
• Force has unit of $\\\tt kgms^{-2}$

Answer 2

Required Answer :-

Refrractive Index

Know More :-

Planck's constant - It is used to measure electromagnetic radiation. Value of Planck's constant is  6.626 × 10⁻³⁴

Speed of light - Speed of light is the speed of light in vaccum or in medium. In vaccum the speed of light is 3 × 10⁸ m/s

Force- A push or pull applied on an object.

Refractive Index - It is the ratio of the speed of light and speed of medium

Dimensions :-

$\sf Planck's \; constant - [ML^2T^{-1}]$

$\sf Speed\; of\; light = [M^0L^1T^{-1}]$

$\sf Force = [MLT^{-2}]$

$\sf Refractive \; Index = M^0L^0T^0$