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Continuing the theme of Center of Mass, this week we’re taking a look at two more popular demonstrations. Demo B1-01 shows us that how an object hangs when suspended is dependent on its center of mass. We can use this to locate the center of mass of an irregularly shaped object, as you see in the picture here.

 B1-01 CENTER OF MASS - DISC SECTION

Demo C1-02, in turn, looks at the center of mass of an irregular object in motion. As this very familiar irregularly shaped object tumbles through the air, its ends seem to be moving every which way. But the center of mass follows a parabolic path, just like a simple thrown ball.

 C1-02: CENTER OF MASS MOTION - PLUMBER'S HELPER

The UNSW School of Physics has some videos analyzing this. You can see how the ends of an object or the limbs of a running athlete move through the air, while the center of mass traces out that same parabolic path. And they found the center of mass of a runner the same way we did with the plunger: just see where it balances!

 https://www.animations.physics.unsw.edu.au/jw/centre.html

B1-05: CENTER OF MASS - PLUMBER'S HELPER