Question

Two right circular cylinders have their diameters equal to their heights. Their volumes are as 3:4. Find the ratio of their heights.

Answer 1

Step-by-step explanation:

Volume of right circular cylinder =πr

2

h

Let height, radius and volume of first cylinder be h

1

,r

1

,v

1

and of second cylinder be h

2

,r

2

,v

2

v

2

v

1

=

πr

2

2

h

2

πr

1

2

h

1

h

2

h

1

=

2

1

;

v

2

v

1

=1;

r

2

r

1

=?

v

2

v

1

=

r

2

2

r

1

2

.

2

1

⇒1=(

r

2

r

1

)

2

=×2⇒(

r

2

r

1

)

2

=2⇒

r

2

r

1

=

2

∴r

1

:r

2

=

2

:1