Question

The speed of light in a certain glass is lod times1.8×,10(8)m/s . define refractive index. What is SI unit of refractive index? find the refractive index of glass.​

Answer 1

we know that refractive index n=

speedoflightinmedium

speedoflightinvacuum

where c=3×10

8

m/s

1.5=

v

c

v=

1.5

3×10

8

v=2×10

8

m/s

For critical angle we will use snell's law

C is critical angle

n

glass

sinC=n

air

sin90 n

air

=1

sinC=

n

glass

1

=

1.5

1

C=41.8

o