2014 · Q89
For the next three (3) items that follow: A right triangle having hypotenuse 25 cm and legs in the ratio 3 : 4 is made to revolve about its hypotenuse. (π = 3.14) Consider the following:
- 1The volume of the cone generated when the triangle is made to revolve about its longer leg is same as the volume of the cone generated when the triangle is made to revolve about its shorter leg.
- 2The sum of the volume of the cone generated when the triangle is made to revolve about its longer leg and the volume of the cone generated when the triangle is made to revolve about its shorter leg is equal to the volume of the double cone generated when the triangle is made to revolve about its hypotenuse.
Which of the above statements is/are correct?
Elementary MathematicsMensuration
- A1 only
- B2 only
- CBoth 1 and 2
- DNeither 1 nor 2
Explanation
About the 20 cm leg: V = (1/3)π·225·20 = 1500π; about the 15 cm leg: V = (1/3)π·400·15 = 2000π — unequal, and their sum 3500π ≠ 1200π.