if rain drops of equal size fall with terminal velocity of 0.50m/s. what will be the terminal velocity if the drops collaspe to form a big drop?

0.25m/s

Explanation:

m1v1 =m2 v2. law of conservation the of momentum. since they smash together to form a big drop M2 =2m1

m1*0.50m/s=2m1*v2

V2= m1*0.50m/s÷2m1

V2= 0.25m/s

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.