angle θB at which the ray emerges from the glass

X rays are typically used to kill off cancer cells, however an issue some radiologists run into is the damage an x-ray may do to surrounding tissue. Because of this, accuracy plays a key role in radiation therapy. Suppose you are a medical physicist, and you have been given the task of choosing a medium with a proper index of refraction to bend the x rays such that they only hit the tumor. Suppose you know that the x ray comes in at an angle of 20 degrees with respect to the normal of your second medium. You know the tumor expands out to 5 degrees on either side of the normal what is the minimum index of refraction needed for the x ray to hit the tumor

A ray of light crosses the boundary between some substance with n = 1.54 and air, going from the substance into air. If the angle of incidence is 29◦ what is the angle of refraction?   Calculate to 1decimal.

A ray of light consisting of blue light (wavelength 480 nm) and red light (wavelength 670 nm) is incident on a thick piece of glass at 80°.  What is the angular separation between the refracted red and refracted blue beams while they are in the glass?  (The respective indices of refraction for the blue light and the red light are 1.4636 and 1.4561.) 0.27° 0.33° 0.36° 0.46° 0.54°

chapter 25: Problem 9: A beam of light moves through a slab of glass as shown in the figure. The index of refraction of the glass is ng = 1.5. The index of refraction of air is na = 1. The incident angle of the light is θi = 44°. a) If the refraction angle of the light at the upper surface of the slab is θ1, express sinθ1 in terms of θi, na, and ng.  b) The incident angle of the light on the lower surface of the slab is θ2. What is the relation between θ1 and θ2?  c) The refraction angle of the light on the lower surface of the slab is θf. Express sin(θf) in terms of θ2, na, and ng.