# what is the velocity of the light in a glass with an index of refraction of 1.38

#### AshokKandwal

Joined Jan 20, 2009
3
what is the velocity of the light in a glass with an index of refraction of 1.38

#### leftyretro

Joined Nov 25, 2008
395
what is the velocity of the light in a glass with an index of refraction of 1.38
The reciprocal of 1.38 ?

Lefty

#### fanta_hanu

Joined Mar 9, 2009
8
refractive index = 1.38(glass)

refractive index = velocity of light in vaccum/velocity of light in medium

Velocity of light in vaccum = 3810^8 met/sec
--> 1.38 = 3*(10)8 / V

--> V= 3*(10)8/ 1.38

--> V = 21.73 * (10)7 met/sec

Hope its clear now..

cheers,
Hanu

#### thatoneguy

Joined Feb 19, 2009
6,359
refractive index = 1.38(glass)

refractive index = velocity of light in vaccum/velocity of light in medium

Velocity of light in vaccum = 3810^8 met/sec
--> 1.38 = 3*(10)8 / V

--> V= 3*(10)8/ 1.38

--> V = 21.73 * (10)7 met/sec

Hope its clear now..

cheers,
Hanu
The Forum has TeX formatting with "Click and Write" functionality built in. In the editor, It is the Sigma at the left of the button bar: Ʃ

Using TeX, The above equations are much more readable, simply quote this post to see the codes used.

$$c \approx 3 \times 10^{8} \frac{m}{sec}$$

$$R_{i} = \frac {c}{V}$$

$$1.38 = \frac {3 \times 10^{8}} {V}$$

$$V \approx \frac {3\times 10^{8}}{1.38}$$

$$V \approx 21.73\times 10^{7}\frac {m}{sec}$$