Why does a pendulum move in a circular path?

[abar45]

My teacher for Physics hns proposed an extra credit bonus if anyone could answer this question dealing with a pendulm. Why does the pendulm move as if it had a mind of its own. Refering to the circular motion the pendulm starts making after a couple seconds. When the pendulm is released to go in a back and forth motion (a straight line) it starts off straight but then starts to make a circular motion, usually counter clockwise. What is the reason in lamens terms for it's circular path. Please!

 

[pseudovector]

I think it's caused by Coriolis force. Take a merry-go-roung for example, revolving at a constant angular velocity. Different part, at different distances from the rotation axis will move at different velocities, so if something moves away or towards the axis, it will feel the speed change, it will experience acceleration. The cause of that acceleration is the Coriolis force.
Since the Earth revolves around itself, then anything that moves towards or away from the Earth will experience the Coriolis force.
For more information:
http://en.wikipedia.org/wiki/Coriolis_effect

 

[quicknote]

The reason for the pendulum's circular motion is due to the forces acting upon it. As the pendulum swings back and forth, it experiences a force called centripetal force, which is directed towards the center of the circular path. This force is caused by the tension in the string or rod that the pendulum is attached to. At the same time, the pendulum is also experiencing the force of gravity, which pulls it towards the center of the Earth. These two forces work together to create the circular motion of the pendulum. Think of it like a ball on a string being swung around in a circle - the string provides the centripetal force while gravity pulls the ball towards the center of the circle. This combination of forces results in the pendulum moving in a circular path. So, in simpler terms, the pendulum moves in a circular motion because of the forces acting upon it.