Saved Bookmarks
| 1. |
ORrom a solid cylinder whosheight and same diameter is hollowed out. Find thethe nearest cm2a solid cylinder whose height is 2.4 cm and diameter 1.4 cm, a conical cavity of thtotal surface area of the remainsolid to |
|
Answer» Ans :- The total surface area of the remaining solid will be 18 cm² Step-by-step explanation: The outer surface area of the cylinder = 2πrh = 2 x 3.14 x 0.7 x 2.4 = 10.55 cm² slant height of the cone, L = √(h² + r²) =√(2.4² + 0.7²) = √6.25 = 2.5 cm hence outer surface area of the cone = πrL = 3.14 x 0.7 x 2.5 = 5.5 cm² This outer surface area of the cone is equal to the inner surface area of the hollow portion of the cylinder left. surface area of the cylindrical base = πr² = 3.14 x 0.7² = 1.54 cm² Hence total surface area of the remaining solid = The outer surface area of the cylinder + inner surface area of the hollow portion of the cylinder left + surface area of the cylindrical base = 10.55 + 5.5 + 1.54 = 17.59 cm² = 18 cm² (rounded off to nearest cm²) Hence the total surface area of the remaining solid will be 18 cm² |
|