Question

a rectangular sheet of paper 40 cm × 25 cm is rolled along the length what is the height of the cylinder

Answer 1

$<i><b><u><r>h = 40 cm when the sheet is rolled 22 cm becomes the circumference of the base circles. circumference = 22 cm 2 π r = 22 cm 2×22/7×r = 22 cm r = 22×1/2×7/22 r = 7/2 r = 3.5 Now we got the radius as 3.5 cm. volume of  a cylinder = π r² h                                = 22/7 × 3.5 × 3.5 × 40                                = 1540 cm³ Therefore volume of the cylinder = 1540 cm³$