Question

two'hemisphere is 462 cm", find its volume.
10. Two cubes each of volume 27 cm are joined end to end to form a solid. Find the surface
area of the resulting cuboid.
11. A right circular cone of radius 3 cm, has a curved surface area of 47.1 cm?. Find the volume​

Answer 1

Total surface area of the hemisphere =462cm

2

Total surface area of the hemisphere =2πr

2

⇒462=3πr

2

⇒r=7 cm

Volume of hemisphere =

3

2

πr

3

V=

3

2

×

7

22

×7

3

V=718.67cm

3

Let the edge of each cube be a cm. It is given that the volume of each cube is 27 cm3. When two cubes are joined end-to-end, the solid obtained is a cuboid whose length, breadth and height are 6 cm, 3 cm and 3 cm respectively. Thus, the surface area of the resulting cuboid is 90 cm2.