Imagine Earth's identical twin planet "Farth" is twice as far away from the Sun as Earth is. Compared to the force of gravity the Sun experiences due to Earth, how strong is the force of gravity the Sun experiences due to Farth? Imagine Earth's identical twin planet "Farth" is twice as far away from the Sun as Earth is. Compared to the force of gravity the Sun experiences due to Earth, how strong is the force of gravity the Sun experiences due to Farth? One-fourth as strong. One-half as strong. The same strength. Twice as strong. Four times as strong.

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.

where is the