What are the conditions for circular motion?

Does v, the tangential velocity have to be constant at all times in circular motion? how can one prove it given the following scenario or otherwise?



and given that a body moves from A to B while performing circular motion in a short time interval t (with an angle of 2theta subtended between the two points where theta is small and measured in radians) how can one prove that there is no tangential acceleration?



these are the issues I have with circular motion, would grealty appreciate some help!! thanks!What are the conditions for circular motion?Does v, the tangential velocity have to be constant at all times in circular motion?



No. If a skateboarder travels in a half-pipe ramp, she is traveling in circular motion. She is traveling along the path of a circle and that is all that is necessary for circular motion. She is traveling slowly at the top of the ramp, and quickly at the bottom of the ramp. Obviously, she is traveling with a varying tangential velocity.



For you second question, I don't really see enough information to prove that there never is tangential acceleration. It is the same challenge as answering the first of this man's question:

http://www.youtube.com/watch?v=0v6kB21Km鈥?/a>



There isn't really enough information, unless you know the details of its kinematics at every point in time.