Answer:
The frequency of the waves depends on the distance between wave fronts - considering a front as a maximum disturbance of the wave
(Consider the waves emitted by an organ pipe: condensation and rarefactions)
The waves themselves are a fixed distance apart -
as one moves towards the source the waves received will be closer together (higher frequency)
So if the frequency received increases, the distance between the source and the observer must be decreasing
I know one is transformed, not sure about another
Answer:
n = 1.4266
Explanation:
Given that:
refractive index of crystalline slab n = 1.665
let refractive index of fluid is n.
angle of incidence θ₁ = 37.0°
Critical angle 
According to Snell's law of refraction:
At point P ; 
Therefore:
Then maximum value of refractive index n of the fluid is:
n = 1.4266
