Find the momentum of a 25kg object going 4 m/s.

Given data

Find momentum (p) = ?

mass (m) = 25 Kg ,

velocity (v) =4 m/s

         momentum (p) = m.v

                                  = 25 × 4

                                  = 100 Kg. m/s

Momentum of the object is 100 Kg. m/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.