Angular velocity - right-hand rule

[BillyCheung]

Dear all

By right - hand rule, if circular motion of the object is anti-clockwise in horizontal circle, so that the centripetial force of it will upward in vertical. In addition, the centripetial force is larger that gravity, then the object will move upward in vertical. Do you agree with my idea? Thank very much. Good Bye

Billy

[Ambitwistor]

Originally posted by BillyCheung
By right - hand rule, if circular motion of the object is anti-clockwise in horizontal circle, so that the centripetial force of it will upward in vertical. In addition, the centripetial force is larger that gravity, then the object will move upward in vertical.

If the object is in counter-clockwise ("anti-clockwise") horizontal circular motion (as viewed from above), then the angular velocity vector will point vertically upward. In the absence of gravity, the centripetal force will be horizontal, in the plane of motion, pointing towards the center of the circle. If you're taking a downward gravitational force into account, then the centripetal force will be inward but also upward. The object will move upward if the vertical component of the centripetal force is greater than the object's gravitational weight.

[Ambitwistor]

Originally posted by Ambitwistor
If you're taking a downward gravitational force into account, then the centripetal force will be inward but also upward.

I was careless: the centripetal force is defined to be in the plane of the circle. So the centripetal force will still be horizontal. However, if you're spinning the object around on a string or something, then you could have a tension force directed inwards and upwards, whose horizontal component is the centripetal force, and whose vertical component is what you're comparing to the gravitational force.