The correct answer is: D. None of these
The center of gravity of a thin hollow cone lies on the axis of symmetry at a height of one-third of the total height above the base.
The center of gravity of a body is the point at which the entire weight of the body can be considered to act. It is located at the intersection of the body’s center of mass and its axis of symmetry.
The center of mass of a body is the point at which the total mass of the body is evenly distributed. It can be found by calculating the average of the coordinates of the mass of each point in the body.
The axis of symmetry of a body is a line through the body such that if the body is rotated about this line, the shape of the body remains unchanged.
In the case of a thin hollow cone, the center of mass is located at the intersection of the cone’s axis of symmetry and its base. The axis of symmetry of a cone is a line that passes through the center of the cone’s base and the apex of the cone. The base of a cone is a circle.
The center of gravity of a thin hollow cone is located at a height of one-third of the total height above the base. This is because the mass of the cone is evenly distributed around the axis of symmetry, and the center of mass is located at the average of the coordinates of the mass of each point in the cone.
The options A, B, and C are incorrect because they do not represent the correct height of the center of gravity of a thin hollow cone above the base.