Answers
Answer:
Diameter of hemisphere = 14cm
r = 14
r = 7cm
CSA of hemisphere = 2tr²
= 2x4x7x7
= 44 x 7 =
= 308cm²
r = 7cm
h (total) 13cm, h (cylinder) = 13 radiusof hemisphere- 13-7-6cm.
CSA of Cylinder,
= 2ærh
= 2x²x7x6
= 44 x 6
= 264cm²
Surface area of the vessel = CSA of Hemisphere + CSA of Cyclinder
= 308 +264
= 572cm²
Step-by-step explanation:
(1) Diameter = 14 cm, radius = d/2 = 14/2 = 7 cm
Height of the cylindrical portion is 6cm (13-7)
Area of a Curved surface of cylindrical portion = 2πrh
Substitute the values,
= 2 × 22/7 ×7 × 6
= 264 cm²
Area of a curved of hemispherical portion = 2πr²
Substitute the values,
= 2 × 22/7 × 7 × 7
= 308 cm²
Hence, the total surface area is (308 + 264) 572cm².
(2) Total surface area of the toy = Curved surface area of the hemisphere + Curved surface area of the cone
Now,
Curved surface area of the hemisphere = 2πr² and Curved surface area of the cone = πrl
Where 'r' is the radius and 'l' is the slant height.
Radius of the hemisphere (r) = 3.5 cm
Height of the hemisphere is equal to the radius of the hemisphere i.e. 3.5 cm. Radius of the cone is also 3.5 cm.
Now,
Height of the cone = Total height of toy - height of hemisphere
= 15.5 cm - 3.5 cm
= 12 cm
Slant height of the cone (l) = √(r² + h²)
= √[(3.5 cm)² + (12 cm)²]
= √(12.25 + 144) cm²
= √ 56.25 cm²
= 12.5 cm
Total surface area of the toy = curved surface area of the hemisphere + curved surface area of the cone
= 2πr² + πrl
= πr (2r + l)
= 22/7 × 3.5 × (2 × 3.5 + 12.5)
= 22/7 × 3.5 × (7 + 12.5)
= 11 × 19.5
= 214.5
Hence, the total surface area of the toy is 214.5 cm².