Question

1) Make a sketch of an object whose center of gravity is not located on the object itself. This a

Answer 1

Boomerang , doughnut

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these are example of body having COG outside body.

Center of gravity is calculated as the point where the force of gravity act, center of mass is constant and COG changes as the body orientation is changed.

a lot of people think that the center of mass is the same as the center of gravity... YOU ARE TOTALLY WRONG. They are only the same for a sphere (because you can actually replace the sphere for a punctual mass) and for constant gravity fields. For example, suppose that the gravity field of the Earth did not vary with

1/r^2

and it was constant then every body in the victinity of earth would have they're center of mass coincident with they're center of gravity. BUT THAT'S NOT THRUTH. So only spheres on earth have it's center of mass coincident with it's center of gravity.

DEFINITIONS: The center of gravity is the place where you would put an infinitesimal small mass (punctual) and it would be atracted by the same force as a bigger body with the same mass.

So, if there is not a body to atract you, you would not have a center of gravity but you would still have a center of mass.

CENTER OF GRAVITY IS CALCULATED AS WHERE THE NET TORQUE DUE TO GRAVITY IS ZERO. THIS IS HOW WE CALCULATE COG.