What is the Speed of a Bead on a Circular Wire in Space?

[p_o_o_k_i]

hey guys! this question is a complete mind boggler to me =[

consider a bead of mass m that is free to move on a thin, circular wire of radius r. the bead is given an initial speed vo, and there is a coefficient of kinetic friction uk. the experiment is perfomred in a spaceraft drifting in space. Find the speed of the bead at any subsequent time t.

http://img291.imageshack.us/my.php?image=80ag3.jpg


my work:
i'm assuming that because it's in space, it experiences a drag force? And it requires some sort of integration? And there is centripetal acceleration.
And that's all i know.

It'd be so great if I could get some help! Thanks so much in advance!

 

[OlderDan]

hey guys! this question is a complete mind boggler to me =[

consider a bead of mass m that is free to move on a thin, circular wire of radius r. the bead is given an initial speed vo, and there is a coefficient of kinetic friction uk. the experiment is perfomred in a spaceraft drifting in space. Find the speed of the bead at any subsequent time t.

http://img291.imageshack.us/my.php?image=80ag3.jpg


my work:
i'm assuming that because it's in space, it experiences a drag force? And it requires some sort of integration? And there is centripetal acceleration.
And that's all i know.

It'd be so great if I could get some help! Thanks so much in advance!

The only "drag" in the problem is from the friction between the bead and the wire. The frictional force is proportional to the normal force, which is the force the wire exerts on the bead to make it follow the circular path. Since the bead slows down, that force will not be constant, so you probably will need to do some calculus.

 

[p_o_o_k_i]

thanks so much! at least now i have a idea where to start! =]