How much iron is needed to make a rod of length 90 cm and diameter 1.4

1.	How much iron is needed to make a rod of length 90 cm and diameter 1.4 cm?
Answer» Given: For cylindrical rod: length of rod (h) = 90 cm, and diameter (d) = 1.4 cm To find: Iron required to make a rod diameter (d) = 1.4 cm ∴ radius (r) = d/2 = 1.4/2 = 0.7 cm Volume of rod = πr²h = (22/7) x 0.7 x 0.7 x 90 = 22 x 0.1 x 0.7 x 90 = 138.60 cc ∴ 138.60 cc of iron is required to make the rod

How much iron is needed to make a rod of length 90 cm and diameter 1.4 cm?

Answer»

Given: For cylindrical rod: length of rod (h) = 90 cm, and diameter (d) = 1.4 cm

To find: Iron required to make a rod diameter (d) = 1.4 cm

∴ radius (r) = d/2 = 1.4/2 = 0.7 cm

Volume of rod = πr²h

= (22/7) x 0.7 x 0.7 x 90 = 22 x 0.1 x 0.7 x 90

= 138.60 cc

∴ 138.60 cc of iron is required to make the rod