What is the kinetic energy of a 3 kg ball that is rolling at 3 m/s?

Explanation:

The mass of the ball is 3 kg.

The velocity of the ball rolling is 3 m/s.

Evaluating and solving for kinetic energy.

The kinetic energy of the ball is 13.5 Joules.

Kinetic energy =1/2mv^2.

1/2×3×3^2.

1/2×27=13.5 or 13 whole number 1/2.

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000

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.