Physic Labs

Problem 3

Light travels from glass of refractive index 1.5 into air. Find the critical angle and condition for total internal reflection. Use the stated ideal model: quantities are constant or vary only as specified, with no extra drag, losses, or external influences. State a sign convention, keep units consistent, and use a classical approximation only where appropriate. (a) Set up the governing equation from a fundamental law. (b) Solve for the requested quantity under the stated conditions. (c) Check the result using a suitable limit, sign, or unit test, and report both the expression and its physical meaning.
ic=41.8∘,r(30∘)=48.6∘,i>ici_c=41.8^\circ,\quad r(30^\circ)=48.6^\circ,\quad i>i_c
problems.proof.analysis

The boxed expressions answer the parts in order. Signs, conditions of validity, and constants follow the conventions in the statement.