Question

if circumference of base of cylinder is equal to twice its height then the volume of cylinder is equal to :

Answer 1

The circumference in this problem is2*height and the circumference formula is 2*pi*radius. In other words:
c = 2h =2*pi*r
Dividing by 2 gives us
h = pi*r
The volume of a cylinder formula is
\[v = \pi * r ^{2} * h\]
Substituting for h yields
\[v = \pi * r ^{2} * (\pi * r)\]
or
\[v = \pi ^{2} * r ^{3}\]