Answer:
The critical angle for the liquid when surrounded by air is 30 degrees.
Explanation:
Given that,
The angle of incidence is 33.5° and the angle of refraction is 19.3°. Firstly, we can find the refractive index of the liquid. It can be calculated using Snell's law as :
[tex]n=\dfrac{\sin i}{\sin r}\\\\n=\dfrac{\sin (33.5)}{\sin (19.3)}\\\\n=2[/tex]
The critical angle is given by :
[tex]\theta_c=\sin^{-1}(\dfrac{n_1}{n_2})[/tex]
Here, [tex]n_1[/tex] is refractive index of air and [tex]n_2[/tex] is refractive index of liquid.
[tex]\theta_c=\sin^{-1}(\dfrac{1}{2})\\\\\theta_c=30^{\circ}[/tex]
So, the critical angle for the liquid when surrounded by air is 30 degrees.
