Simple planetary gearsets are being discussed. Technician A says any one of the three members can be used as the driving or input member. Technician B says the ring gear is always the driving or output member. Who is correct?

Technician A- any of the three members can be used as the driving or input member.

Explanation: The three members which can be used as a driving or input member are sun gear, pinion gear carrier, and ring gear, hence, the carrier and its pinions are seen as one unit which is the mid-size gear member. However, One member can be held and kept from rotating while the third member becomes the output member or the driven. Selecting which member is driving, held and driven determines the gear ratio for the gearset.

0.55x745.7j and a calculator

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.