(c) If you want the beam to undergo total internal reflection at the second interface (the interface between sheet 1 and the air), what is the minimum angle the incoming beam (the beam traveling in the sheet 2) must make with the x-axis

33.749

Explanation:

According to the given situation, the solution of the minimum angle is shown below:-

We will apply the law to no and n1 medium  which is

After solving the above equation we will get

= 33.749

Therefore for computing the minimum angle we simply applied the above formula.

Hence, the correct answer is 33.749

grav potential energy