A ray of light is incident on a glass slab making an angle of $60^{0}$ with the surface. Calculate the angle of refraction in glass and the velocity of light in glass if the refractive index of glass and the velocity of light in air are 1.5 and 3.0 x 10 $^{8}$ m/s respectively.
$28^{\circ} 30^{'}$ , $3 \times 10$ $^{8}$ ms $^{- 1}$
$35^{\circ} 15^{'}, 2 \times 10^{8}$ ms $^{- 1}$
$40^{\circ} 20^{'}, 2.5 \times 10$ $^{8}$ ms $^{- 1}$
$28^{\circ} 30^{'}, 2.5 \times 10^{8}$ ms $^{- 1}$

Question

A ray of light is incident on a glass slab making an angle of $60^{0}$ with the surface. Calculate the angle of refraction in glass and the velocity of light in glass if the refractive index of glass and the velocity of light in air are 1.5 and 3.0 x 10 $^{8}$ m/s respectively.
$28^{\circ} 30^{'}$ , $3 \times 10$ $^{8}$ ms $^{- 1}$
$35^{\circ} 15^{'}, 2 \times 10^{8}$ ms $^{- 1}$
$40^{\circ} 20^{'}, 2.5 \times 10$ $^{8}$ ms $^{- 1}$
$28^{\circ} 30^{'}, 2.5 \times 10^{8}$ ms $^{- 1}$

Toppr Admin · Accepted Answer

Using Snell-apos-s law -x3BC-1sin-xA0-i-x3BC-2sin-xA0-r1-xD7-sin60-x2218-1-5-xD7-sin-xA0-rr-35-x2218-15-x2032-And Vglass-c-x3BC-3-xD7-1081-5-xA0-m-s-2-xD7-108-xA0-m-s

Using Snell's law :μ1sin i=μ2sin r1×sin60∘=1.5×sin rr=35∘15′And Vglass=cμ=3×1081.5 m/s=2×108 m/s

Using Snell's law :

$μ_{1} s i n i = μ_{2} s i n r$

$1 \times s i n 60^{\circ} = 1.5 \times s i n r$

$r = 35^{\circ} 15^{^{'}}$

And $V_{g l a s s} = \frac{c}{μ}$

$= \frac{3 \times 10^{8}}{1.5} m / s$

$= 2 \times 10^{8} m / s$