Carbon disulfide (n = 1.63) is poured into a container made of sodium chloride (n = 1.54). what is the critical angle for total internal reflection of a light ray in the liquid when it is incident on the liquid-to-glass surface?

70.87°

Explanation:

The formula for the critical angle is:

Where,  

is the critical angle

is the refractive index of the refractive medium.

is the refractive index of the incident medium.

n₁ is the refractive index for Carbon disulfide which is 1.63 (incident medium)  

n₂ is the refractive index of sodium chloride which is 1.54 (refractive medium)

Applying in the formula as:

The critical angle is = sin⁻¹ 0.9448 = 70.87°

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =