Question

two right circular cylinder are formed by rolling the rectangular aluminum sheets which is formed by the dimensions of 12m length and 5m breadth one by rolling along its length another by rolling along its breadth. find the ratio of csa​

Answer 1

Answer:

Length of rectangular sheet = 12m

Breadth of rectangular sheet = 5m

when the sheet is rolled along its length , heigth of cylinder(H) = 12m

and circumference of the circular region = 5m

when the sheet is rolled along its breadth, heigth of cylinder = 5m

and circumference of the circular region = 12m

2πr = 5 (when the sheet is rolled along its length)

2 x 22/7 x r = 5

R = 35/44 m

2πr = 12 (when the sheet is rolled along its breadth)

2 x 22/7 x r = 12

r = 21/11 m

C.S.A of the cylinder when rolled along the length =(C1) =  2πrh

C1 = 2 x 22/7 x 35/44 x 5

C1 = 175/7 m²

C.S.A of the cylinder when rolled along the breadth = (C2) = 2πrh

C2 = 2 x 22/7 x 21/11 x 12

C2 = 1008/7 m²

Ratio of C1 and C2 = (175/7) ÷ (1008/7)

= 175/1008

= 175:1008