Question

The volume of a 1-metre iron rod is 1386 cu. cm. find its diameter

Answer 1

0.42 cm will be the answer

Answer 2

Volume = Height x Area

Height of the rod= 100 cm

Area = $\pi$ x (r)^2

volume = 1386 = 100 x ($\pi$ x (r)^2)

13.86 = $\pi$ (r)^2

r^2= 4.411

r= 2.1 cm

diameter = 2.1*2 = 4.2 cm

Hope this helps