Question

Q. If the height and radius of a cone of volume v are doubled, find the volume of cone.




Urgent

Answer 1

let r = radius of the original cone

h = heught of the original cone

V = volume of the original cone

= 1 /3 × pi × r^2 × h

Since radius and height gets doubled , then

R = new radius = 2 x r = 2r

H = new height = 2 × h = 2h

New volume

= 1 / 3 × Pi × R^2 × H

= 1/3 × Pi × ( 2r ) ^2 × ( 2h )

= 1/3 × Pi × 4 × r^2 × 2h

= { 1/3 × Pi × r^2 × h } × 8

= 8 × Volume of the original cone

Answer 2

answer:

let the original height be h

let the original radius be r

then according to the question:

height of cone= 2h

radius of cone = 2r

volume of cone =1/3πr²h

= 1/3 ×22/7×4r²×2h

= 4×2[1/3×22/7×r²×h]

=8[1/3 πr²h] square unit

thus the volume will be 8 times the original volume .

hope this helps