Content

• Steps
• Advice
• What you need

A sphere is a perfect three-dimensional circular object, each point on its surface being equally spherical. In life, there are many common objects with spheres like balls, globes, and so on. If you want a volume of a sphere, you need to find its radius, then apply the radius to the simple formula, V = ⁴⁄₃πr³.

Steps

1. 

   Write down the formula for the volume of the sphere. We have: V = ⁴⁄₃πr³. In which, "V" represents volume and "r" represents the radius of the sphere.

2. 

   
   
   Find the radius. If the radius is available then we can go to the next step. If the problem gives you diameters, if you want to find the radius you just need to divide the diameter in half. Once you have the data, write it down on paper. For example, we have a spherical radius of 1 cm.
   • If you only have the area of ​​the sphere (S), to find the radius, divide the area of ​​the sphere by 4π, and then calculate the square root of this result. That is, r = √ (S / 4π) ("the radius is equal to the square root of the quotient of area and 4π").

3. 

   
   
   Calculate the cubic power of the radius. To do this, you simply multiply the radius by itself or triple it. For example, (1 cm) is actually 1 cm x 1 cm x 1 cm. The result of (1 cm) is still 1 because how many times 1 multiplied by itself is still 1. You will have to rewrite the unit of measure (here centimeters) after you come up with your answer. When you're done, plug the value r³ into the original spherical volume formula, V = ⁴⁄₃πr³. In this example, we have V = ⁴⁄₃π x 1.
   • For example, if the radius is 2 cm, after the third power of the radius we have 2, it is 2 x 2 x 2 or 8.

4. 

   
   
   Multiply the cubic power of the radius by 4/3. Substitute r, or 1, into the formula V = ⁴⁄₃πr³, then multiply to make the equation more compact. 4/3 x 1 = 4/3. Now our formula will be V = ⁴⁄₃ x π x 1, good V = ⁴⁄₃π.

5. 

   Multiply the expression by π. This is the last step to finding the spherical volume. You can leave π in your answer in the same format V = ⁴⁄₃π. Or, you put π in the calculation and multiply its value by 4/3. The value of π is equivalent to 3.14159, so V = 3.14159 x 4/3 = 4.1887, you can round to 4.19. Don't forget to conclude with the units of measure and return the results to cubic units. Thus, the volume of the sphere with radius 1 is 4.19 cm. advertisement

Advice

• Don't forget to use cubic units (eg 31 cm³).
• Make sure that the quantities in the problem have the same units of measure. If not, you will have to convert them.
• Note, the symbol " *" is used as a multiplication sign to avoid confusion with the variable "x".
• If you want to calculate a part of a sphere, such as a quarter or quarter, find the total volume first, then multiply that volume by the fraction you are looking for. For example, a sphere has a total volume of 8, to find the volume of a half sphere, you have to multiply 8 times ½ or divide 8 by 2, the result is 4.

What you need

• Calculator (reason: to calculate complex calculations)
• Pencil and paper (not necessary if you have an advanced computer)