InterviewSolution
Saved Bookmarks
| 1. |
A hollow cylinder of height 21 cm and volume 7276.5 cm3 circumscribes a cone having the same base as the cylinder. The CSA of the cone is half of the CSA of the cylinder. Find the height of the cone.1. 162. 173. 184. 19 |
|
Answer» Correct Answer - Option 3 : 18 GIVEN: Height of hollow cylinder = 21cm Volume of hollow cylinder = 7276.5 cm3 CSA of the cone = 1/2 × CSA of the cylinder FORMULAS USED: Volume of cylinder = \(% MathType!MTEF!2!1!+- % feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeqiWdahaaa!37B0! π \)π r2h CSA of cylinder = 2π rh CSAof cone = π rl EXPLANATION: Volume of cylinder \(\pi\)r2h = 7276.5 \(\frac{22}{7}\times r^2\times21 = 7276.5\) \(r^2 = \frac{7276.5}{66} = 110.25\) r = 10.5 Since the base of cone and cylinder is same the radius of the cone is also 10.5 now, CSA of cone = \(\frac12\)CSA of cylinder \(\therefore π rl = \frac122π rh\) \(\rightarrow\) l = h l = 21 now, height of cone h2 = l2 - r2 h2 = 212 - 10.52 h = 18
|
|