Question

9.
If the height and the radius of a cone are doubled, the volume of the cone becomes
(1) 2 times
(2) 4 times
(3)
6 times
(4) 8 times​

Answer 1

Answer:

let the Height of the cone=h am

Radius of the cone=r cm

Then volume of the cone=

3

1

πr

2

h

If the height and radius are double then

Height=2h

Radius=2r

Then new volume=

3

1

π(2r)

2

×2h

⇒

3

1

π×4r×2h=8×

3

1

πr

2

h

Hence it is 8 times of the old volume