Centre of Mass Trick

A video showing how you can balance an object on a single point by giving support exactly below center mass of the object.
Here are few more tricks on same principle. 

See how I balanced few kitchen items on their center of mass :)

Cups balanced perfectly without adding water. But remember to take cups with wider side edge (coke can has wide edge hence it is easy to balance by adding water). Try balancing tumbler with very thin edge, it will be very difficult. I hope you can understand why it is so.