Which one is most important in explaining the tremendous tidal heating that occurs on io?
a. io is the closest to jupiter of jupiter's large moons.
b. io orbits jupiter on an elliptical orbit as a result of orbital resonances with other satellites.
c. io exhibits synchronous rotation, meaning that its rotation period and orbital period are the same.
d. io orbits jupiter in the io torus, and therefore has a surface that is bombarded by many charged particles.

The correct answer is B

Explanation:

The reason is because Io orbits Jupiter on an elliptical orbit as a result of orbital resonances with other satellites.

The orbit resonances is a phenomena whereby one objects orbit period is a simple ratio of another object's period such as 1/2, 5/3, etc. What really happened is that during this period, the two objects line up to each other and the extra-gravitational pull will influence their orbits, and causes tidal friction which is then the source of the tremendous internal heating.

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.