Sunlight passes into a raindrop at an angle of 22.5° from the normal at one point on the droplet. What is the angle of refraction?

1 Answer
Jul 24, 2017

I got #16.7^@#

Explanation:

Consider the diagram:
enter image source here

We can use Snell's Law to find the angle of refraction #theta#:

#n_0sin(theta_0)=nsin(theta)#

where:
#n_0=1# index of refraction of air;
#theta_0=22.5^@# angle of incidence;
#n=1.33# index of refraction of water (from literature).

We get rearranging:
#sin(theta)=n_0/nsin(theta_0)#
#theta=arcsin[n_0/nsin(theta_0)]#
#theta=arcsin[1/1.33sin(22.5^@)]=16.7^@#