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Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Bidyut sinha Best Answer
ANSWER IS RING. Another example is BOOMERANG(An weapon of Australia) EXPLANATION:-As we know that center of mass is a Concept where it is supposed that all Mass of the body is concentrated on that point. It is NOT CERTAIN thing that center of mass should lie inside the body; it's NOT MANDATORY CONDITION.. For some object (you may tell hollow object), all the mass of the body is supposed to be concentrated on center of mass point and that's outside (Such as ring , hollow object, boomerang). So for Ring, its center of mass is supposed to be concentrated at its center , which is out side the body.