A solid hemisphere is mounted on a cylinder of equal radius. The total height of the combined solid is 6R. Find the total surface area.
Show answer & explanation
Correct answer: A
Explanation
Radius of the cylinder and hemisphere = R
Total height of the combined solid = 6R
Therefore, height of the cylinder = 6R − R = 5R
Total surface area = Curved surface area of the cylinder + Curved surface area of the hemisphere + Area of the cylinder's base
= 2πR(5R) + 2πR² + πR²
= 10πR² + 2πR² + πR²
= 13πR²