25 circular plates, each of radius 10.5 cm and thickness 1.6 cm, are p

1.	25 circular plates, each of radius 10.5 cm and thickness 1.6 cm, are placed one above the other to form a solid circular cylinder. Find the curved surface area and the volume of the cylinder so formed.
Answer» Radius of each circular plate = 10.5 cm Thickness of each plate = 1.6 cm 25 plates are placed one above the other to form a solid circular cylinder ∴ height of the cylinder formed, h = 25 × 1.6 cm = 40 cm Total curved surface area of the cylinder = 2πrh = \(2\times\frac{22}{7}\times10.5\times40\) = 2640 cm² Volume of cylinder = πr² h = π (10.5)² × 40 = 13860 cm³

25 circular plates, each of radius 10.5 cm and thickness 1.6 cm, are placed one above the other to form a solid circular cylinder. Find the curved surface area and the volume of the cylinder so formed.

Answer»

Radius of each circular plate = 10.5 cm

Thickness of each plate = 1.6 cm

25 plates are placed one above the other to form a solid circular cylinder

∴ height of the cylinder formed, h = 25 × 1.6 cm = 40 cm

Total curved surface area of the cylinder = 2πrh

= \(2\times\frac{22}{7}\times10.5\times40\)

= 2640 cm²

Volume of cylinder = πr² h

= π (10.5)² × 40

= 13860 cm³