Snell's law: n1Sinα=n2Sin β where α=Incidence angle, β=angle of refraction, n1 and n2 are the indices of refraction for water and air respectively.
Therefore,
Sinα=n2/n1 Sinβ For refracted ray to be along the surface of water, β=90° and thus Sinβ = 1
Sinα=n2/n1= 1/1.33 = 0.7519 => α=sin^-1 (0.7519) = 48.75°
When light moves from a medium of higher index of refraction (such as water) to medium of lesser index of refraction (such as air), the refracted ray is bend such that α is bigger than β. This is internal refraction. At some value of α, β approaches 90°. This incidence angle is called critical incidence angle. Therefore, the current scenario is shows critical angle of incidence.
Answer:

Explanation:
Given that,
The radius of a bend, r = 20 m
Velocity of motorcyclist, v = 3 m/s
The combined mass of motorcyclist and the motorcycle is 50 kg
We need to find the motorcyclist’s centripetal acceleration. The formula used to find the centripetal acceleration is given by :

So, the acceleration of the motorcyclist is
.
apple, earth. earth more massive than moon. astronauts showed this - armstrong etc
The answer I believe would be a sorry if I’m wrong