How to Find the Volume of a Sphere?

Spheres are three-dimensional renditions of circles. Spherical entities of different kinds surround us; in fact, we live on planet Earth, a gigantic oblate spheroid, while another much more gigantic sphere, our star Sun, is the reason life on Earth exists. Most celestial bodies are spherical, thanks to gravity. Here, on Earth, we can find spheres nearly everywhere, from baseballs, footballs, and golf balls to water bubbles, certain fruits, bulbs, etc.

Studying the area and volume of a sphere is fundamental to the study of geometric shapes in mathematics, physics, and engineering. Its properties are studied in electrostatics. If you go on to have a career in astronomy, you will be studying them in much more detail. Spheres appear in the form of ball bearings in mechanical engineering, as well as parts of superstructures, buildings, ships, aircraft, etc. Spheres form a critical part of studies & applications in earth sciences, materials science, lighting systems engineering, nanotechnology, medical imaging, climate studies, and more. All in all, the study of spheres has always been and will forever be integral to mat,s science & engineering.

This article, as evident from the title, dwells deep into a crucial feature of spheres & spherical bodies – their volume. Read on to learn everything about how to find the volume of a sphere, a hemisphere/half-sphere, and all essential formulae through detailed explanations, examples, & exercises.

Let’s dive right in.

What is the Volume of a Sphere?

Well, the volume of any sphere, or any three-dimensional object for that matter, is the amount of space occupied by or contained within its boundaries. Also referred to as the capacity of an object, finding volumes and areas of objects such as spheres is fundamental in mathematics.

• Every point on the surface of a sphere is equidistant from its center. This distance is known as the
• Twice the radius equals the diameter of a sphere. The diameter is the longest straight line that passes through its center and connects opposite points on the surface. The end-points of the diameter are called
• Standard mathematical practices and conventions refer to the surface of a spherical entity to be a sphere. The inside, though colloquially referred to as a sphere, is aptly referred to as a ball.
• The volume of a solid sphere is NOT the same as that of a hollow sphere and depends mainly on the thickness of the material of the sphere. The case is the same with hemispheres or half-spheres.

The following sections take a look at the formula for volume of a sphere, volume of a half sphere as well as the volume of a hollow sphere. We will be taking a look at them closely through some examples and practice problems.

The Formula for the Volume of a Sphere

The formula for finding the volume of a sphere of radius R is given as

V = (4/3) * π * R³

Where π is the universal constant with a value of 3.1415927

The infamous Greek polymath Archimedes derived this formula, and he considered this discovery to be one of his biggest achievements. Did you know that you can derive the volume of a sphere formula using calculus and the Pythagoras theorem?

How to Find the Volume of a Sphere? Common Questions & Problems

If you are wondering how to find the volume of a sphere, then it’s quite easy, really. The formula is quite simple to use. All you need to know is the radius of the sphere, and you are good to go.  

• For example, if you have a spherical ball of diameter 42 centimeters, then its volume comes to something around →

V = (4/3) * π * (21)

or, V  =  38792.39609 cm³

The value of π is taken as 3.1441442.

• Here’s another one.

Say the diameter of a solid spherical ball is 14 centimeters. Then, if we have to find the amount of material contained within the sphere, we have to find the volume. Now, there would be certain instances where you might be asked to express the answer in terms of π. 

In this case, the answer would go something like this →

V= (4/3) * π * 7³

Or, V= 457.334 π

• Again, if you are asked to work with π value of 3.14 and are asked to find the volume of a ceramic bowl of radius 25 cm, then you will have to use the formula for finding the volume of a hemisphere.

Finding the volume of a hemisphere is no big deal.

R = 25, π = 3.14

V = [(4/3) * π * (25/2)]/2

or  V= [(4/3) * 3.14 * 12.5]/2

Or, V= 23.167 cm³

There are certain common real-life applications of finding the volume of spheres and hemispheres. You need to learn about the volume when deciding the amount of material necessary to craft a solid spherical object of a particular diameter and surface area. You will also have to find the volume to determine the time taken to fill the entirety of a sphere and hemisphere

Here are two such common applicational problems.

• A solid ball bearing has a diameter of 6 cm. Its total mass is 1.2 kg. What should be the density of the material in terms of π?
• A hemispheric container of radius 500cm. Water is filling the container at the rate of 500 cm³ per minute, How long will it take to fill the bowl?

There are simple problems that you can solve easily if you know the formula for the volume of a sphere.  Try to solve them as quickly as possible. 

Next up are a few advanced problems in finding the volume of a hemisphere,  the radius of a sphere when given the volume, as well as the volume of a hollow sphere.

Advanced Topics

• Volume of a Half-Sphere or Hemisphere

All you need to do is divide the volume of a sphere by two. That will give you the volume of a hemisphere. Here’s the formula →

V = [(4/3) * π * R] / 2

or V = (⅔) * π * R

• Finding the Radius from the Volume

Wondering how to find the radius of a sphere when given the volume? Well, it is quite simple, really. All you need to do is manipulate the volume equation a bit and then put in the given values.

The original equation is V = (4/3) * π * R³

Rearranging, we get,  

∛ (3V /4π) = R

Finding the Volume of a Hollow Sphere/Volume of Material of a Hollow Sphere

• The volume of a hollow sphere is also the amount of material contained within that sphere. If the outer radius is R and the inner radius is r, then the volume is calculated using the formula →

V= (4/3) * π  * (R-r)³

• To find the volume contained within a hollow sphere, all we need to do is find the volume of the inner hollow.

V = (4/3) * π * r³

Like any other topic, concept, problem type, or domain in math, the only surefire ways to master are intelligent problem-solving and diligent practice. Below are some practice and example problems for you to try your hand at.

Examples and Practice Problems

1. Calculate the inner and outer radii of a hollow sphere of thickness 8 cm and volume 240 cm³.
2. A sphere has a radius is 9 cm. Calculate the volume in terms of π.
3. A solid globe has a diameter of radius 30 centimeters.  Find its volume. If its mass is 2.8 kg., find the density of the material used. 
4. Given the volume of a sphere is 10000 cubic inches, find its radius to the nearest decimal plane. Use 3.14 as the value of π. ( 1 meter = 100 cm. = 39.3 inches)
5. A sphere has a distance of 2 meters between its antipodes. It is completely immersed in water. Calculate the amount of water it displaces.
6. The outer diameter of a hollow sphere is 28 cm, while its inner diameter is 14 cm. How much material can be obtained after melting it>
7. If the diameter of a sphere is 8 feet, then find out its volume. Take the value of π as 3.142 and round off the answer to two decimals. 
8. What is the volume of the largest sphere carved out of a cube of edge 6 cm? The volume of a cube is calculated by raising the value of the cube’s side to the power of 3.
9. If the ratio of the diameters of two cubes, then what could be the ratio of their volumes?
10. If the diameter of a sphere is reduced by ⅓, then by how much will its volume go down?

Solve the above problems as quickly as possible and look for similar problems for practice. Do so diligently, and you will surely be able to ace any kind of problem on the volume of spheres.

Visual Aids

• Here’s a half sphere of radius 20 mm →

• Below is a hollow sphere with an inner radius r and an outer radius of R →

• Below is another collage on spheres.

• Here’s a hemispherical bowl of radius 25 cm.

Here’s a graphical representation of the volume calculation process of a sphere.

And that brings us to near the end of this write-up. We conclude everything with a quick round-up of the essential points about volumes of spheres.

Conclusion

• The volume of a sphere is calculated using the following formula  (4/3) * π * R³
• You can find the volume of a hemisphere with → (⅔) * π * R³
• Spheres are three-dimensional representations of circles.
• The end-points of a sphere’s diameter are called antipodes.
• The volume of a hollow sphere is also the amount of material that the sphere contains. It is given as  (4/3) * π * (R – r)³, where R is the outer radius and r is the inner radius.
• Spheres and spherical objects find widespread applications in astronomy, manufacturing, metallurgy, meteorology and architecture. The volume and surface area of spherical objects play major roles in every one of them.

Well, that rounds up this write-up. Hope this was an interesting and informative read for everyone. Practice different problems on spheres and if you need any kind of help with solving them, then connect with the math experts of MyAssignmentHelp.com.

All the best

FAQs

● What is the formula for the volume of a sphere?

The formula for finding the volume of a sphere is as follows →

V = (4/3 ) * π * R³

where  π is a universal constant, and R is the radius of the sphere

● How do you find the volume of a sphere with a given radius?

You find the volume of a sphere with a given radius with the formula given above, V = (4/3) * π * R³ 

● What is the volume of a sphere with a diameter of X?

Calculate the radius of the sphere by dividing the diameter by 2.  Then, use the above formula to calculate the volume.

● How to calculate the volume of a sphere using π?

Quite simple, really. You follow the same formula for finding the volume of a sphere (4/3) * π * R³. The only thing is that you replace π with any value and calculate the answer in terms of π.