Center of Gravity

We have been…

Can we…?

What path did they follow? Both follow a parabolic path But bat wobbles around a certain point Center of Gravity This point follows a parabolic path The rest does not Center of Gravity is at the center of weight distribution

Symmetrical  geometrical center Not Symmetrical  toward heavier end Wobbling Toys  Dense Bottom

Wobble Toys

Center of Gravity Sometimes called Center of Mass Point of average mass distribution For objects near – interchangeable In space, center of mass (NOT gravity) Center of Gravity of Moon Closer to Earth than the center of mass Nearer parts pulled more by Gravity But for everyday objects - same

Center of Gravity Center of Gravity of Meter Stick Point where balance Entire weight behaves as if concentrated at one point

Finding Center of Gravity Suspend an object and mark with a vertical line Change point of suspension and mark 2 nd line Point of intersection is the Center of Gravity

Center of Gravity Center of Gravity may be where no material is…

Lean Back?

Toppling – Why? “Weeble Wobble Theorem” An object whose center of gravity is above its base of support will not topple If center of gravity outside area of support  topple

Designs Low Center of Gravity and Wide Base

Balancing Toys Weighted so Center of Gravity vertically under support point with the remainder above

Center of Gravity and People When you stand straight up, center of gravity in the body is 2-3 cm below belly button and centered between the front and back Center of gravity lower in women

Center of Gravity and People Touch Toes – Where is the Center of Gravity?

Center of Gravity and People When Standing Center of gravity above support base (area bounded by feet) Baby Trouble coordinating center of gravity above feet when walking

Center of Gravity Stand on Toes Smaller Base Pregnant Woman Lean backwards so center of gravity is above the base Pigeon Jerks head so center of gravity is above supporting base

More Examples