Finding a relationship for the ball's speed with the following clues.

[GreenTea09]

Homework Statement

A ball rolls around a horizontal circle at height y inside the cone shown below. Find an
expression for the ball’s speed in terms of r(radius of cone),x(height of cone),p and g(9.81ms^-2).

Homework Statement

r(radius of cone),x(height of cone),p and g(9.81ms^-2).

The Attempt at a Solution

i came across this question from a friend's tutorial but i stared at it whole day. can't think of any solutions,cant think of even where to start.

i tried using the variable g to form any possible relationship i could think of but the ball is moving in a horizontal circle..

 

[MuIotaTau]

I would start by drawing a force diagram. What forces are acting on the ball? Which forces have to sum to zero?