Check all that apply. the center of gravity of a triangular solid with uniform thickness and density
a. the point at which one can balance the triangle.
b. the point shared by a triangle's altitudes.
c. the centroid.
d. the orthocenter.

Aplayground merry-go-round has a radius of 4.6 m and a moment of inertia of 200 kg-m2 and turns with negligible friction about a vertical axle through its center. a child applies a 26.0 n force tangentially to the edge of the merry-go-round for 15.0 seconds. if the merry-go-round is initially at rest, how much work did the child do on the merry-go-round?