Answer:
a) θ = 65º , b) the light is refracted
Explanation:
When a ray of light passes from a material with a higher index to one with a lower index, the ray separates from the normal one, so there is an angle for which the ray is refracted at 90º, the refractive equation is
n₁ sin θ₁ = n₂
where θ₁ is the incident angle, n₂ and n₁ are the indexes of incident and refracted parts
let's calculate
sin θ = n₂ / n₁
sint θ = 1.3333 / 1.470
sin θ = 0.907
θ = sin⁻¹ 0.907
θ = 65º
For the incident angle of 50.2º it is less than the critical angle, so the light is refracted according to the refraction equation
Weak winds that blow for short periods of time with a short fetch.
Answer:
From Newton's 2nd Law, we have 
. Substituting given values, we have:
U = 0, initial vertical velocity
v = 60 mph = 88 ft/s
Ignore air resistance and take g = 32 ft/s².
It t = time to attain 60 mph, then
(88 ft/s) = (32 ft/s²)*(t s)
t = 88/32 = 2.75 s
Answer: 2.75 s
