How to Calculate the Mass of a Material for a Hollow Spherical Shell?

[chanv1]

What mass of a material with density p is required to make a hollow spherical shell having inner radius r1 and outer radius r2?

How do I get the volume of the hollow sphere without any numbers?

Any help would be greatly appreciated!

 

[atyy]

What mass of a material with density p is required to make a hollow spherical shell having inner radius r1 and outer radius r2?

How do I get the volume of the hollow sphere without any numbers?

Any help would be greatly appreciated!

Give your answer in terms of p, r1 and r2. To start, find the volume of the hollow sphere in terms of r1

 

[chanv1]

I know the volume of a hollow sphere is V = 4/3 pi r^3. But how do I get the answer in terms of p, r1, and r2 without having any given numbers?

 

[atyy]

I know the volume of a hollow sphere is V = 4/3 pi r^3. But how do I get the answer in terms of p, r1, and r2 without having any given numbers?

V = 4/3 pi r^3 is the volume of a sphere, hollow or not.

Give your answer in terms of p, r1, and r2, not in terms of any given numbers (which are not given).

Equivalently, you may treat p, r1 and r2 as your "given numbers".

 

[Wesli]

Your answer won't be an integer, but will contain "r₁, and r₂." Where you would normally put the numerical value of these unknowns, you leave them as "r₁," and "r₂."

It also might be more helpful to think of "volume of the hollow sphere," as the "volume of the spherical shell." The volume of a sphere is 4/3πr³, while the volume of a spherical shell is...

 

[chanv1]

Thanks for the help!