How does the "Centre of Gravity' affect you in your sport / hobbies ? In the things we try to build e.g. bridges, playground equipment, houses ... sooo what happens in an earthquake? what can we do to reduce damage caused by changes in the centre of gravity and momentum ... Go Kids ... Get researching and thinking.

O K ...................

 Sooo  ... what has FRICTION and the CENTRE OF GRAVITY go to do with the 

"Christmas Tree Challenge?" ... a bit of fun to finish the year.
https://youtu.be/Fxg_zL3qJyk