The sum and difference off the outer and inner radii of hollow cylinder are 5 cm and 2 cm respectively. If the height of the cylinder is 1.4 cm, find its (a) curved surface area (b) total surface area (c) volume.
Answers
Answer:
hi
Step-by-step explanation:
Sol. Volume of each cube = 64 cm3
∴ Total volume of the two cubes = 2 × 64 cm3
= 128 cm3
Let the edge of each cube = x
∴ x3 = 64 = 43
∴ x = 4 cm
Now, Length of the resulting cuboid l = 2x cm
Breadth of the resulting cuboid b = x cm
Height of the resulting cuboid h = x cm
∴ Surface area of the cuboid = 2 (lb + bh + hl) = 2[(2x . x) + (x . x) + (x . 2x)]
= 2[(2 × 4 × 4) + (4 × 4) + (4 × 2 × 4)] cm2
= 2 [32 + 16 + 32] cm2
Sol. For cylindrical part:
Radius (r) = 7 cm
Height (h) = 6 cm
∴ Curved surface area
= 2πrh
For hemispherical part:
Radius (r) = 7 cm
∴ Surface area = 2πr2
∴ Total surface area
= (264 + 308) cm2 = 572