About
An open source physics at Singapore simulation based on codes written by Fu-Kwun Hwang and Loo Kang WEE.
more resources can be found here
http://iwant2study.org/ospsg/index.php/interactive-resources/physics/02-newtonian-mechanics/04-turning-effects-of-forces

Introduction
Property of a body for which a small angular displacement set up a restoring torque that tends to return the body to its original position. In a rotational mechanical equilibrium the angular momentum of the object is conserved and the net torque is zero. An important property of systems at mechanical equilibrium is their stability.

Instruction
Drag the center of the block to make the block tilt with an angle. As long as the center of gravity stay inside the surface area of the object on the ground, the block will not fall out. Because the torque will always turn it back.
However, if the center of gravity was outside the surface area, the block will fall out.! You can also change width or height (resize) of the block within the simulation.

Interesting Fact
This simulation has a 2D view targeted for O level Physics education, and is open sourced. http://iwant2study.org/ospsg/index.php/interactive-resources/physics/02-newtonian-mechanics/04-turning-effects-of-forces/362-blocktiltedwee

Acknowledgement
My sincere gratitude for the tireless contributions of Francisco Esquembre, Fu-Kwun Hwang, Wolfgang Christian, Félix Jesús Garcia Clemente, Anne Cox, Andrew Duffy, Todd Timberlake and many more in the Open Source Physics community.