Ethan and Rebecca are riding on a merry-go-round. Ethan rides on a horse at the outer rim of the circlar platform, twice as far
from the center of the circular platform as Rebecca, who rides on an inner horse. When the merry-go-round is rotating at a constant angular speed, describe Ethans tangential speed?
Let be the distance from the center of the platform to Rebecca's horse, Rebecca's tangential speed, the Ethan's tangential speed and the merry-go-round angular speed. The distance from the center of the platform to Ethan's horse is . The angular speed is related to the tangential speed by the equation:
Since the angular speed is the same for Ethan and Rebecca, we have that:
Now, solving for we get:
It means that Ethan's tangential speed is twice as Rebecca's.
I would say Option B) because Option C) is wrong since matter cannot be created. A closed system does not exchange matter so it's not Option D). Since an island is an isolated area, Option A) is wrong.