The force of gravitation between two cricket balls is extremly small but that between a cricket ball and earth is extremly is large?

Explanation:

Gravitational force depends upon the product of masses of the object. Earth has siginificantly greater mass than cricket ball. The product of masses for two ball is very low as compared to the product of earth and ball mass. That is why the gravitational force between earth and ball is relatively larger than two balls.

The force of gravitation between the earth and the ball is large than the two balls.

Explanation:

The force of gravitation between the two bodies is directly proportional to the product of masses of two bodies and inversely proportional to the square of the distance between them.

So, when we take cricket balls , the masses of balls is very small and the distance is also small so the force between the two balls is small.

When we take earth and the ball, the mass of earth is very large eve distance is very large so the force between the earth and the ball is large as compared to the two balls.  

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.