Question

the radius of a cylinder is doubled and height remains same the ratio between volumes of new cylinder and orginal cylinder is?

Answer 1

here is your answer.

Answer 2

Let the radius of cylinder be r
and height be h

Volume of Cylinder = πr²h

Now,

New radius = 2r
but height remains the same

So,

New Volume = π ( 2r )²h

=> 4πr²h

• Ratio of old volume to the new Volume

$\frac{vol \: of \: old \: cylinder}{vol \: of \: new \: cylinder} = \frac{\pi {r}^{2} h}{4\pi {r}^{2} h}$

$\frac{vol \: of \: old \: cylinder}{vol \: of \: new \: cylinder} = \frac{1}{4}$

So,

ratio of volume of old cylinder to the new cylinder is 1 : 4


and

Volume of new cylinder to the old cylinder is
4 : 1