If the ball is in equilibrium position, total forces works on the ball equals to zero,

The ball is then brought to an arbitrary position, so its position vector is

Hence, the total forces works on the ball are

Substitute from equation (1), and we can get

From the picture above, we can conclude that this system is the same as a system with a spring attached to the ball's equilibrium point without gravitational force.
Because in the new system there's no gravity, we can conclude that the highest position of the ball is at the other side, point A (see picture above).

Substitute and from equation (1) and (2) to equation (5),

And now we can get the coordinate,

That's my solution.
If you have any question, correction, or comment, please leave a comment below.
Thank you.

Solution - Spring and Hanging BallSocialTwist Tell-a-Friend


arnab banerjee said... @ June 24, 2011 at 9:20 AM

the ball will go back to the direction of the spring and bounce twice in the wall (assuming the spring is attached to a wall) and lastly stay at the bottom of the wall. the coordinate of the ball is (x=0, y=1).

Post a Comment