(879,#13) Find the mass and center of mass of the solid S bounded by the paraboloid and the plane if S has constant density K.

Solution: When a = 1 the solid S has the shape of a sausage:

As for its center of mass:

Going on to the centroid:

Center of mass:

Since the region is symmetric with respect to the x and y axis .

Going on to the y-coordinate:

Since the mass is , the center of mass is , which is plausible, for most of the mass of the sausage is in its upper part.

Maple code

by:sh