Answer:
Let the second medium be air (n₁=1)
The refractive index n₂ of the medium where first medium is air is found (a)
(a) n₂ = 2
Explanation:
Critical angle can be defined as the angle of incidence that provides the angle of refraction of 90°.
Refractive index of a medium can be defined as a number that describes that how fast a light will travel through that medium.
Critical angle and Refractive index are related by:


To find refractive index of medium with respect to air, substitute n₁=1 (Refractive index of air is 1)
Also θ(critical)=30°
Find n₂ :

This would be typical of an elastic collision.
Answer:
The tunnel probability for 0.5 nm and 1.00 nm are
and
respectively.
Explanation:
Given that,
Energy E = 2 eV
Barrier V₀= 5.0 eV
Width = 1.00 nm
We need to calculate the value of 
Using formula of 

Put the value into the formula


(a). We need to calculate the tunnel probability for width 0.5 nm
Using formula of tunnel barrier

Put the value into the formula


(b). We need to calculate the tunnel probability for width 1.00 nm


Hence, The tunnel probability for 0.5 nm and 1.00 nm are
and
respectively.