Question

find the area of the sheet required to make a cylindrical container which is open at one side whose diameter is 28 cm and height is 20cm find the approximate area of the sheet required to make a lid of height 2 cm for this container​

Answer 1

Step-by-step explanation:

For cylindrical container:

diameter (d) = 28 cm

height (h1) = 20 cm

For cylindrical lid:

height (h2) = 2 cm

diameter (d) = 28 cm

∴ radius (r) = d/2 = 28/2 = 14 cm

i. Surface area of the cylinder with one side open = Curved surface area + Area of a base

2πrh1 + πr^2

= πr (2h1 + r) = (22/7) x 14 x (2 x 20 + 14)

= 22 x 2 x (40 + 14)

= 22 x 2 x 54 = 2376 sq.cm

Area of sheet required to made a lid = Curved surface area of lid + Area of upper surface

= 2πrh + πr^2

= πr (2h + r) = (22/7) x 14 x (2 x 2 + 14)

= 22 x 2 x (4 + 14) = 22 x 2 x 18 = 792 sq cm