# How to find the mass of a sphere in a problem

• Confusedalot1
In summary, to determine the mass of a sphere, you can use the formula V = (4/3)πr^3 to find its volume and then multiply it by the density of the material the sphere is made of. This formula can also be written as V = (4/3)πd^3, where d is the diameter of the sphere. However, this formula is only applicable if the density of the material is known. To convert the radius or diameter of a sphere from one unit to another, you can use the conversion factor for that specific unit. When calculating the mass of a hollow sphere, you will need to account for the difference in density between the hollow and solid parts.

#### Confusedalot1

Two spheres are placed so that their centers are 2.5 m apart. The force between the two spheres is 2.70 10-12 N. What is the mass of each sphere if one sphere is twice the mass of the other sphere?
1 . ______kg (lighter sphere)
2 ._______ kg (heavier sphere)

the equation i used:
Fg= (G)(m1)(m2)/r^2

I got

1. .25
2. .5

but the answer was wrong. does anyone know how to plug this in correctly?

Show exactly what you plugged in where.

## 1. How do I determine the mass of a sphere?

The mass of a sphere can be determined by multiplying its volume by its density. The formula for the volume of a sphere is V = (4/3)πr^3, where r is the radius of the sphere. Once you have the volume, you can then multiply it by the density of the material the sphere is made of to find the mass.

## 2. What is the formula for finding the volume of a sphere?

The formula for finding the volume of a sphere is V = (4/3)πr^3, where r is the radius of the sphere. This formula can also be written as V = (4/3)πd^3, where d is the diameter of the sphere.

## 3. Can I use the same formula to find the mass of any sphere?

No, the formula for finding the mass of a sphere is only applicable if the density of the material is known. If the density is not known, you will not be able to accurately determine the mass of the sphere.

## 4. How do I convert the radius or diameter of a sphere from one unit to another?

To convert the radius or diameter of a sphere from one unit to another, you can use the conversion factor for that specific unit. For example, to convert from centimeters to meters, you would divide the value by 100. It is important to make sure that all units are consistent when using the formula to find the mass of a sphere.

## 5. Can I find the mass of a hollow sphere using the same formula?

Yes, you can still use the formula V = (4/3)πr^3 to find the volume of a hollow sphere. However, when calculating the mass, you will need to take into account the difference in density between the material making up the hollow part and the material making up the solid part of the sphere. You can then add the masses of the two parts together to find the total mass of the hollow sphere.