Practicing Success
A cone, a hemisphere and a cylinder stand on equal bases and have the same height. What is the ratio of their volumes? |
1 : 2 : 3 2 : 3 : 1 3 : 2 : 1 3 : 1 : 2 |
1 : 2 : 3 |
The correct answer is Option (1) → 1 : 2 : 3 For same base and height of Cone, cylinder and hemisphere, height of cone and cylinder, h = radius of hemisphere, r = base radius of cone and cylinder, rb Volume of Cone V1= \(\frac{1}{3}\)π \( {rb}^{2} \) h = \(\frac{1}{3}\)π \( {r}^{3} \) Volume of hemisphere V2= \(\frac{2}{3}\)π \( {r}^{3} \) = \(\frac{2}{3}\)π \( {r}^{3} \) Volume of Cylinder V3= π \( {rb}^{2} \) h = π \( {r}^{3} \) V1:V2:V3 :: \(\frac{1}{3}\) : \(\frac{2}{3}\) : 1 = 1:2:3 |