Question

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 1

Answer:

25 circular plates

Radius of plate = 10.5 cm

thickness = 1.6 cm

curved surface Area = (?)

volume of cylinder = (?)

→ Height of the cylinder =no.ofplates×thickness

=25×1.6

=40cm

→ curved surface Area =2πr.h

=2π×10.5×40

=2,640cm

2

→ volume of the cylinder =πr

2

.h

=π×(10.5)

2

×40

=13.860cm

3