Question

. A rectangular sheet of paper 30 cm x 18 cm can be transformed into the curved surface area of a right circular cylinder into two ways either by rolling the paper along its length or by rolling it along its breadth. Find the ratio of the volumes of the two cylinders thus formed

Answer 1

Here, when the cylinder is rolled from bredth,
h=18cm and
circumference of the base=30cm
=>22/7*r^2=30cm. -(1)
Now, volume of the cylinder=22/7*r^2*h
=>30*18 By (1)
=>540cm^2
Similarly when it is rotated by length,
h=30cm and
circumference of the base=18cm
=>22/7*r^2=18 -(2)
Now, volume of the cylinder=22/7*r^2*h
=>30*18 By (2)
=>540cm^2
Ratio of their volumes=540/540
=1:1