Question

Radius of a cylinder is r and the height is h. Find the change in the volume if the height is doubled and the radius is halved.

Answer 1

∵ Volume of a cylinder = πr²h

Where, h is height and r is radius of base of the cylinder.

If height is doubled and the radius is halved,

i.e. h = 2h and `r = r/2`

∴ Volume = `pi xx (r/2) xx (r/2) xx 2h`

= `pi xx r^2/4 xx 2h`

= `(pir^2h)/2`

Hence, volume became half of the original volume.