1. The problem statement, all variables and given/known data I was trying to learn about this force, and came across a youtube video: . At 4.00 in the video, he says, "if the parcel of air continues to get deflected..." Why would it continue to get deflected? At 4.40 in the video, a girl rolls a ball while moving on a merry go round, and the ball ends up forming a circle and coming back to her. Why does this happen? 2. Relevant equations I think I'm supposed to use conservation of angular momentum here. So MVR+I*omega is constant. 3. The attempt at a solution I don't understand how the parcel could continue to get deflected and end up changing direction, and forming a circle. I thought that coriolis effect was observed by people on earth because air packets in motion on the equator are faster than those closer to the poles, so moving towards the poles, they would have a higher speed than the earth there, and thus appear to get deflected towards the east. But once reaching there, do they get deflected back to the equator, like shown in the video? If so, how do they gain the velocity towards the equator? Is it because of conservation of angular momentum, because they have a higher velocity with a lower radius now and need to increase the radius again, and so they move towards the equator? As for the girl on the merry go round, she rolls the ball, and with respect to the merry go round, it rotates in a circle. How does that happen? Is it due to conservation of angular momentum, again? And how to prove that its a perfect circle?