Surface area of a shape made of a hemisphere and cone

Question

a solid shape is made from a cone on top of a hemisphere. Base of cone has a 6cm radius and vertical height of 8cm. Hemispheres radius is 6cm. work out the total surface area of the shape to 3 significant figut

Answer 1

Think about breaking the overall shape down into shapes that you know--or parts of shapes that you know.

 

A hemisphere is half of a sphere, so the surface area of the hemisphere part will be half the surface area of a sphere.

 

The surface area of a sphere can be found in your textbook or online.

 

The cone part of the shape is missing its base, so take the formula for surface area of a cone (from textbook or online) and subtract from that the area of the cone's base (a circle) to get the surface area of the cone part.

 

Then add together the surface area of the cone part and the surface area of the hemisphere part, and you're done!