If it a right cone then it is a circle, otherwise an ellipse.
Circle
When a cone is sliced by a slanted plane, the cross section formed is typically an ellipse. The exact shape can vary depending on the angle and position of the plane relative to the cone. If the plane is parallel to the cone's base, the cross section will be a circle; if it intersects the cone at a steeper angle, the resulting shape will be an ellipse.
A cross section of a right circular cone is a two-dimensional shape obtained by slicing the cone perpendicular to its axis. Depending on the position of the cut, the cross section can be a circle, an ellipse, or a triangle. If the cut is made parallel to the base, the cross section will be a smaller circle. If the cut is made vertically through the apex and perpendicular to the base, it will form a triangle.
By definition, the circular cross-section of a cone changes linearly in width as you go along its axis. By definition, the cross-section of a prism is constant along its axis. So, by definition, a cone prism is an impossible shape.
For a right cone, it is a hyperbola which becomes and isosceles triangle when the section passes through the apex.
The vertical cross section of a right vertical cone is a triangle if that cross section is taken from the vertex. Any other vertical cross section will reveal a hyperbola (with endpoints on the base of the cone). A link can be found below.
Circle
The answer depends on the angle at which the axis of the cone intersects the cross-sections.
Circle
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A circular cross-section.
cone
A cross section of a right circular cone is a two-dimensional shape obtained by slicing the cone perpendicular to its axis. Depending on the position of the cut, the cross section can be a circle, an ellipse, or a triangle. If the cut is made parallel to the base, the cross section will be a smaller circle. If the cut is made vertically through the apex and perpendicular to the base, it will form a triangle.
By definition, the circular cross-section of a cone changes linearly in width as you go along its axis. By definition, the cross-section of a prism is constant along its axis. So, by definition, a cone prism is an impossible shape.
Depends on the way you cut the cone, but the outline is either an ellipse or a parabola.
For a right cone, it is a hyperbola which becomes and isosceles triangle when the section passes through the apex.
The strongest shape in nature is the triangle. A traffic cone has a cross section of a triangle. This would give it strength especially when knocked into by the traffic.