# [Urgent] Need help with physics question

#### sk8erboi

##### New member
Hello,

I'm unsure if this is the right forum, so i apologize in advance. I'm trying to make sense of this physics question:

A cylindrical tank holds 100,000 L of water. How much water could a tank hold if it had dimensions that were double that of the first tank?

This is not an algebra question, it's a proportionality question. I was wondering if someone could explain how to solve this, or direct me to resources that would help me understand the concepts involved in this question.

Thanks

#### Subhotosh Khan

##### Super Moderator
Staff member
Hello,

I'm unsure if this is the right forum, so i apologize in advance. I'm trying to make sense of this physics question:

A cylindrical tank holds 100,000 L of water. How much water could a tank hold if it had dimensions that were double that of the first tank?

This is not an algebra question, it's a proportionality question. I was wondering if someone could explain how to solve this, or direct me to resources that would help me understand the concepts involved in this question.

Thanks
Do you know the equation for volume of a cylinder (circular base) with

height =h

and

diameter = D?

#### Jomo

##### Elite Member
Hello,

I'm unsure if this is the right forum, so i apologize in advance. I'm trying to make sense of this physics question:

A cylindrical tank holds 100,000 L of water. How much water could a tank hold if it had dimensions that were double that of the first tank?

This is not an algebra question, it's a proportionality question. I was wondering if someone could explain how to solve this, or direct me to resources that would help me understand the concepts involved in this question.

Thanks
As Subhotosh Khan has said you need to know the volume of a cylindrical tank. It will be in terms of the radius, r, and the height, h. What will the volume be if we doubled h and r. Can you continue from here?

#### sk8erboi

##### New member
As Subhotosh Khan has said you need to know the volume of a cylindrical tank. It will be in terms of the radius, r, and the height, h. What will the volume be if we doubled h and r. Can you continue from here?
Yep, got it, thank you

If anyone wants to know how i solved it just let me know

#### Harry_the_cat

##### Senior Member
Hello,

I'm unsure if this is the right forum, so i apologize in advance. I'm trying to make sense of this physics question:

A cylindrical tank holds 100,000 L of water. How much water could a tank hold if it had dimensions that were double that of the first tank?

This is not an algebra question, it's a proportionality question. I was wondering if someone could explain how to solve this, or direct me to resources that would help me understand the concepts involved in this question.

Thanks
In a 2D shape, if the dimensions are doubled (x2), then the area will be increased by a factor of 2^2 (ie x4).

In a 3D shape, if the dimensions are doubled (x2), then the volume will be increased by a factor of 2^3 (ie x8).

Can you see why?

#### mmm4444bot

##### Super Moderator
Staff member
… If anyone wants to know how i solved it just let me know
There may be future readers who'll be interested (years from now, for example). Please consider posting your work right away, while it's still fresh in your memory. :cool: