Question

refractive index of water is4/3 then caluculate the speed of light in water

Answer 1

Solution :

⏭ Given:

✏ Refractive index of water = 4/3

⏭ To Find:

✏ Velocity of light in water

⏭ Concept:

✏ Refractive index of a medium is defined as ratio of light in vacuum to the velocity of light in medium.

⏭ Calculation:

$\mapsto \sf \: \mu = \dfrac{velocity \: of \: light \: in \: vacuum}{velocity \: of \: light \: in \: medium} \\ \\ \mapsto \sf \: \dfrac{4}{3} = \dfrac{3 \times {10}^{8} }{V_w} \\ \\ \mapsto \sf \: V_w = \dfrac{3 \times {10}^{8} \times 3}{4} \\ \\ \mapsto \underline{ \boxed{ \bold{ \sf{ \pink{ \large{V_w = 2.25 \times {10}^{8} \: mps}}}}}}$

⏭ Additional information:

• Refractive index is unitless quantity.
• Refractive index is dimensionless quantity.

Answer 2

$\huge \mathtt{ \fbox{Solution :)}}$

Given ,

• Refractive index of water = 4/3

We know that ,

The ratio of speed of light in vacuum to the speed of light in medium is called refractive index of medium

$\large \mathtt{\fbox{Refractive \: index = \frac{speed \: of \: light \: in \: vaccum}{speed \: of \: light \: in \: medium} }}$

Thus ,

4/3 = 3 × (10)^8/speed of light in water

speed of light in water = (3 × 3 × (10)^8)/4

speed of light in water = (9 × (10)^8)/4

speed of light in water = 2.25 × (10)^-8 m/s

Hence , the speed of light in water is 2.25 × (10)^-8 m/s

______________ Keep Smiling ☺