A laser beam traveling in air ( ) strikes a flat slab of crown glass ( ) at an angle…

PHYSICS · Single correct · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction

Problem

A laser beam traveling in air (

n=1.00

) strikes a flat slab of crown glass (

n=1.52

) at an angle of

40^{\circ}

measured from the normal. Which of the following best describes the relationship between the incident angle

\theta_{\text{air}}

and the refracted angle

\theta_{\text{glass}}

? (a)

\theta_{\text{glass}}>\theta_{\text{air}}

because light slows down in the glass. (b)

\theta_{\text{glass}}<\theta_{\text{air}}

only if

\theta_{\text{air}}

exceeds the critical angle. (c)

\theta_{\text{glass}}<\theta_{\text{air}}

because light slows down in the glass. (d)

\theta_{\text{glass}}=\theta_{\text{air}}

because the interface is planar.