Save today on Math U See. Multi-Sensory homeschool math curriculum. Low price ** Unter einer Sphäre versteht man in der Mathematik die Oberfläche einer Kugel und die Verallgemeinerung davon auf beliebig hohe Dimensionen**. Von erheblicher Bedeutung für viele Untersuchungen ist hierbei die Einheitssphäre, also die Oberfläche der Einheitskugel im n-dimensionalen euklidischen Raum The sphere appears in nature when a surface wants to be as small as possible. Examples include bubbles and water drops. Can you think of more? Volume and Surface Area. Surface Area = 4 × π × r

In Geometry, a sphere is defined as the set of all points in space that are equidistant from a fixed point (the center) of the sphere Sphere. A sphere is defined as the set of all points in three-dimensional Euclidean space that are located at a distance (the radius ) from a given point (the center ). Twice the radius is called the diameter , and pairs of points on the sphere on opposite sides of a diameter are called antipodes Sphere. Sphere. In geometry, a sphereis a solid, that is absolutely round in shape defined in three-dimensional space (XYZ space). Mathematically, a sphere is defined as the set of points that is at equal distances from a common point in three dimensional space

A sphere is a geometrical object in three-dimensional space that is the surface of a ball. Like a circle in a two-dimensional space, a sphere is defined mathematically as the set of points that are all at the same distance r from a given point in a three-dimensional space. This distance r is the radius of the ball, which is made up from all points with a distance less than r from the given point, which is the center of the mathematical ball. These are also referred to as the. What is a sphere? A sphere is a three-dimensional object that is round like a ball and every point on the surface is equidistant (equal distance) from the center

Math explained in easy language, plus puzzles, games, worksheets and an illustrated dictionary. For K-12 kids, teachers and parents ** In mathematics, the Riemann sphere, named after Bernhard Riemann, is a model of the extended complex plane, the complex plane plus a point at infinity**. This extended plane represents the extended complex numbers, that is, the complex numbers plus a value ∞ for infinity. With the Riemann model, the point ∞ is near to very large numbers, just as the point 0 is near to very small numbers. The extended complex numbers are useful in complex analysis because they allow for.

Sphere - Die Macht aus dem All (Originaltitel Sphere) ist ein US-amerikanischer Science-Fiction-Film aus dem Jahr 1998 des Regisseurs Barry Levinson nach dem Roman Sphere - Die Gedanken des Bösen von Michael Crichton aus dem Jahr 1987 SplashLearn is an award winning math learning program used by more than 40 Million kids for fun math practice. It includes unlimited math lessons on number counting, addition, subtraction etc side of the sphere, the sides of a spherical triangle will be restricted between 0 and π radians. The angles will also be restricted between 0 and π radians, so that they remain interior. To derive the basic formulas pertaining to a spherical triangle, we use plane trigonometry on planes related to the spherical triangle. For example, planes tangent to the sphere at one of the vertices of. Try This Example. View MATLAB Command. Specify the radius and location of a sphere by modifying the returned X, Y, and Z coordinates. Define X, Y, and Z as coordinates of a unit sphere. [X,Y,Z] = sphere; Plot the unit sphere centered at the origin. surf (X,Y,Z) axis equal To draw the sphere using the returned coordinates, use the surf or mesh functions. [X,Y,Z] = sphere (n) returns the x -, y -, and z - coordinates of a sphere with a radius equal to 1 and n -by- n faces. The function returns the x -, y -, and z - coordinates as three (n+1) -by- (n+1) matrices. sphere ( ___) plots the sphere without returning the.

aaryansukhadia624 History of Math | Pure Math | Set Theory and Logic One of the greatest paradigm shifts in mathematics took place in 1931, when a mathematician named Kurt Gödel uncovered a striking truth within the ver A sphere (from Greek σφαίρα — sphaira, globe, ball,) is perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point **Sphere**, In geometry, the set of all points in three-dimensional space lying the same distance (the radius) from a given point (the centre), or the result of rotating a circle about one of its diameters. The components and properties of a **sphere** are analogous to those of a circle sphere das Ressort Pl.: die Ressorts sphere der Einflussbereich sphere das Himmelsgewölbe Pl.: die Himmelsgewölbe sphere der Interessenbereich sphere der Wirkungsbereich Pl.: die Wirkungsbereiche sphere [MATH.] die Sphäre Pl.: die Sphären sphere [MATH.] die Kugelfläche Pl.: die Kugelflächen [Geometrie] sphere der Kreis Pl.: die Kreise sphere diagram [TECH.

- The goal of this puzzle is to separate the spheres into tubes conatining a single color. You can move a sphere to an empty tube or to a tube that has the same color sphere on top. Tap on a tube to remove a sphere then tap another tube to release it. Can you solve all 50 puzzles
- En géométrie dans l'espace, une sphère est une surface constituée de tous les points situés à une même distance d'un point appelé centre. La valeur de cette distance au centre est appelée le rayon de la sphère. La géométrie sphérique est la science qui étudie les propriétés des sphères. La surface de la Terre peut, en première approximation, être modélisée par une sphère dont le rayon est d'environ 6 371 km. Plus généralement en mathématiques, dans un.
- SPHERE | from Musical Math Vol. 1. Watch later. Share. Copy link. Info. Shopping. Tap to unmute. If playback doesn't begin shortly, try restarting your device. Up Next
- A sphere is a perfectly round geometrical 3D object. The formula for its volume equals: volume = (4/3) * π * r³. Usually, you don't know the radius - but you can measure the circumference of the sphere instead, e.g., using the string or rope. The sphere circumference is the one-dimensional distance around the sphere at its widest point
- A sphere is a perfectly round three-dimensional object. This lesson will give a mathematical definition of a sphere, discuss the formulas associated with spheres and finish with a quiz
- SUBSCRIBED. Professeur de mathématiques en lycée (Académie de Strasbourg), je partage : - une chaîne YouTube : près de 1500 vidéos pour t'aider à t'améliorer en maths. - un site www.maths.

Derivation of Sphere Volume and Surface Area Formulas Currently in math class we are discussing surface areas and volumes of solids. I would like to know why the volume formula for the sphere is (4/3)*pi*r^3 and why the surface area formula is 4*pi*r^2. I understand why the volume formula contains pi, and radius, and is cubed, but I do not. Viewed 31k times. 26. So coming from a flash background I have an OK understanding of some simple 2D trig. In 2d with I circle, I know the math to place an item on the edge given an angle and a radius using. x = cos (a) * r; y = sin (a) * r; Now if i have a point in 3d space, i know the radius of my sphere, i know the angle i want to position. This circumference of a sphere calculator will figure out the circumference of any sphere given the radius, the diameter, the surface area, or the volume of the sphere. Terminology Sphere - A three dimensional object contained by a surface that has all points at the same distance from the center. Basically, it's something that has a perfectly. ** The Riemann Sphere**.** The Riemann Sphere** is a representation of the compactified (with infinity) complex plane on the sphere with center (0,0,1/2) and radius 1/2. It uses the so-called stereographic projection from the north pole (0,0,1) through the sphere to the x-y-plane of points (x,y,0). A little geometry reveals the following equation >function px(x,y,z) &= x/(1-z) x ----- 1 - z >function.

Like a sphere, a diameter of a hemisphere is any chord that passes through its center, as shown below. Great circle. A great circle is a circle formed when a plane intersects a sphere through its center. It divides a sphere into two equal halves, known as hemispheres. One of the hemispheres for a sphere is shown above. The great circle of the. Know what is Sphere and solved problems on Sphere. Visit to learn Simple Maths Definitions. Check Maths definitions by letters starting from A to Z with described Maths images Sphere. A sphere is a solid bounded by a surface all points of which are equally distant a point within, called center.. A radius is the distance between the center and the surface.. A diameter of a sphere is a straight line drawn through the center, having its extremities in the surface.. Formula

Sphere. A sphere is the set of all points in a space equidistant from a given point called the center of the sphere. The distance between any point of the sphere and its centre is called the radius. The inside of a sphere is called a ball. A spherical cap is a portion of a sphere cut off by a plane. where h is the height of the spherical cap, r. Math explained in easy language, plus puzzles, games, quizzes, videos and worksheets. For K-12 kids, teachers and parents General Equation of Sphere. A sphere is a geometrical object in three-dimensional space that resembles the surface of a ball. Similar to a circle in two-dimensional space, a sphere can be mathematically defined as the set of all points that are at the same distance from a given point

- Times Tables. Print out The Times Tables and stick them in your exercise book. Test Your Tables with an interactive quiz. Play with the Properties of the equation of a straight line. Visit the Math Sphere Forum. Math Tools :: Math Links. Mathematics is commonly called Math in the US and Maths in the UK
- Juan Carlos Ponce Campuzano. Volume of Spheres with Proof. Activit
- Play Sorting Spheres at Math Playground! Sort the colored spheres into contaoners of the same color. Advertisement. 1st Grade. 2nd Grade. 3rd Grade. 4th Grade. 5th Grade. 6th Grade . Fun Games for Kids The goal of this puzzle is to separate the spheres into tubes conatining a single color. You can move a sphere to an empty tube or to a tube that has the same color sphere on top. Tap on a tube.
- For math, science, nutrition, history, geography, engineering, mathematics, linguistics, sports, finance, music Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels

three.js. docs example * If every vertex of the 3V sphere represents a carbon atom, then the sphere represents the molecule called Buckminsterfullerine which really exists, and has some v ery useful chemical and physical properties*. Figure 7: The 2V Dome and Sphere All the domes displayed in Figures 5 and 4 are fairly complicated to build; the easiest that can reasonably be called a geodesic dome is the 2V. homotopy n-spheres, n # 3, 4, are h-cobordant if and only if they are diffeomorphic. Thus for n # 3, 4 (and possibly for all n) the group O, can be described as the set of all diffeomorphism classes of differentiable structures on the topological n-sphere. These facts will not be used in the present paper. 2. Construction of the group On First we give a precise definition of the connected sum. A sphere is inscribed in the cone (the intersection of their boundaries consists of a circle and one point). The ratio of the surface of the ball and the contents of the base is 4: 3. A plane passing through the axis of a cone cuts the cone in an isoscele. Gas sphere. The gas tank has the shape of a sphere with a diameter of 14 m

View MATLAB Command. Specify the radius and location of a sphere by modifying the returned X, Y, and Z coordinates. Define X, Y, and Z as coordinates of a unit sphere. [X,Y,Z] = sphere; Plot the unit sphere centered at the origin. surf (X,Y,Z) axis equal. Define X2, Y2, and Z2 as coordinates of a sphere with a radius of 5 by multiplying the. Sphere Facts. Check out our sphere facts and learn some interesting information about spheres, the three dimensional polyhedron shaped like a ball. Find out what a hemisphere is, what makes spheres special and learn some formulas to help you find the area and volume of a sphere. Read on and enjoy our sphere facts and trivia before taking a look at all our other interesting information devoted.

- The Math Behind the Fact: Well, no, it is not a coincidence. For the ball, a small change in radius produces a change in volume of the ball which is equal to the volume of a spherical shell of radius R and thickness (delta R). The spherical shell's volume is thus approximately (surface area of the sphere)*(delta R). But the derivative is.
- sphere in Maths topic. From Longman Dictionary of Contemporary English sphere sphere / sf ɪə $ sfɪr / AWL noun [countable] 1 ROUND a ball shape 2 AREA OF KNOWLEDGE, DUTIES, STUDY ETC a particular area of activity, work, knowledge etc in the sphere television's increasing role in the political sphere public/private sphere Women have often been excluded from positions of power in the.
- Learn
**Sphere**topic of**Maths**in details explained by subject experts on vedantu.com. Register free for online tutoring session to clear your doubts - Practice applying the volume formulas for spheres. If you're seeing this message, it means we're having trouble loading external resources on our website. If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked. Courses. Search. Donate Login Sign up. Search for courses, skills, and videos. Main content. Math 8th grade Geometry Volume.

- Step 1 : Because soccer ball is in the shape of sphere, we can use the formula of volume of a sphere to find volume of the soccer ball. Write the formula to find volume of a sphere. V = 4/3 · π r 3 ----- (1) Step 2 : To find the volume, we need the radius of the sphere. But, the diameter is given, that is 24 cm. So, find the radius
- A cylinder is similar to a prism, but its two bases are circles, not polygons. Also, the sides of a cylinder are curved, not flat. A cone has one circular base and a vertex that is not on the base. The sphere is a space figure having all its points an equal distance from the center point
- Sphere definition is - the apparent surface of the heavens of which half forms the dome of the visible sky. How to use sphere in a sentence

- Euler's formula for the sphere. Roughly speaking, a network (or, as mathematicians would say, a graph) is a collection of points, called vertices, and lines joining them, called edges.Each edge meets only two vertices (one at each of its ends), and two edges must not intersect except at a vertex (which will then be a common endpoint of the two edges)
- Find 49 ways to say SPHERE, along with antonyms, related words, and example sentences at Thesaurus.com, the world's most trusted free thesaurus
- sphere x2 +y2 +z2 = a2 lying in the ﬁrst octant (x,y,z,≥ 0). Solution. Once again, we begin by ﬁnding n and dS for the sphere. We take the outside of the sphere as the positive side, so n points radially outward from the origin; we see by inspection therefore that (8) n = xi +yj +zk a, where we have divided by a to make n a unit vector. To do the integration, we use spherical coordinates.
- Math > Geometry > Volume > Sphere; Volume of a Sphere Worksheets. The volume of a sphere and hemisphere worksheets meticulously created for 8th grade and high school students help them learn the know-how of calculating the volume of spheres with a set of practice exercises offering integer and decimal dimensions with two levels of difficulty. Find the volume of spheres and hemispheres and find.
- GED Math : Volume of a Sphere Study concepts, example questions & explanations for GED Math. CREATE AN ACCOUNT Create Tests & Flashcards. Home Embed All GED Math Resources . 4 Diagnostic Tests 263 Practice Tests Question of the Day Flashcards Learn by Concept. Example Questions ← Previous 1 2 3 Next → GED Math Help » Geometry and Graphs » 3-Dimensional Geometry » Volume of a Sphere.

- Math Operation; Calculate Sphere Volume (Ball Volume) Calculate Sphere Volume(Ball Volume) * Radius ( R) Unit. Sphere Volume Calculator What is Sphere ? A sphere is a perfectly round geometrical object in 3-dimensional space. It can be characterized as the set of all points located distance r (radius) away from a given point (center). Formula For Volume of Sphere. Volume (V) = 4/3 * π * r 3.
- After doing a ray-sphere intersection I know a point (XYZ) in 3D space that is on the sphere (the exact position in 3D space where the line pierces the sphere hull). For my program I'd like to calculate the Latitude and Longitude of the XYZ point on the sphere, but I can't think (or Google) up a way to do this easily
- The sphere with center O and radius R is the locus of the points of space located at distance R from O. It is therefore the surface generated by the revolution of a circle around its diameter, which is a limit case of torus. NSC: surface all the points of which are umbilics.. The sphere is a surface homeomorphic to the Alexandroff compactification of the plane , written

* @Rishabh Katiyar: The 2nd image leaves some space between the spheres at the center amd uses another central instead of parallel projection*.In addition it looks, like only spehere on the surface are created. Please try to implement this by your own Sphere. Sphere:A sphere is formed by revolving a semi-circle about its diameter.It has one curved surface which is such that all points on it are equidistant from a fixed point within it, called the centre. Length of a line segment joining the centre to any point of the curved surface is called the radius(r) of the sphere. Formula:

You can write your topic however you want, but you need to answer these questions: What do you want to achieve? I want to be able to generate spheres using math. What is the issue? I do not know the math used to generate spheres. I only know the math for a circle. What solutions have you tried so far? I have tried asking in various discords. Circle Generation. local Radius = 1 local Circle. Dyson Sphere Program: Power & Production Math Stuff Guide. This guide is mostly for beginners or people who are too lazy to do the math stuff in this game (Short)terms i use in this Guide - TPS = Thermal Power Station(s) - AM/AMs = Assembling Machine(s) - Lab(s) = Matrix Lab(s) - Miner(s) = Mining Machine(s) - Power Pole(s) / PPole(s) = Tesla Tower(s) Power Grid Math Stuff with. Math › Geometry › 3-D shapes › Sphere › Quiz. Quiz yourself on shapes Take the quiz > Sphere. A sphere is shaped like a ball. It can be hollow or solid. Single surface. A sphere has one continuous surface. Perfect spheres have smooth surfaces where every point is the same distance from the centre. In real life, spherical objects can be rough or bumpy. Hemisphere. If you slice a sphere. Volume and surface area help us measure the size of 3D objects. We'll start with the volume and surface area of rectangular prisms. From there, we'll tackle trickier objects, such as cones and spheres

Volume and Surface Area of a Sphere. TES Resource contributor of the year 2014 - not really a shop, more a free-for-all take what you want and use it however you like! Pupils learn to calculate the volume and surface area of spheres using the relevant formulae. There is a selection of harder questions to challenge the more able on the sheet sphere(ax, ___) 将图形绘制到 ax 指定的坐标区中，而不是当前坐标区中。指定坐标区作为第一个输入参数。 示例. 全部折叠. 显示单位球面. 打开实时脚本. 创建并绘制一个半径等于 1 的球面。使用 axis equal 可沿每个坐标方向使用相等的数据单位。 sphere axis equal. 指定球面半径和位置. 打开实时脚本. 通过.

Math; Algebra; Pre Algebra; Math (Pre-Test and Quiz) Introduction to the Volume of a Sphere. STUDY. Flashcards. Learn. Write. Spell. Test. PLAY. Match. Gravity. Created by. Lyssabug13 . got 77% on the Pre-Test, so I'm including the questions on the quiz, too, which I got 90% really hope this helps someone!! /(. n.)\ Terms in this set (20) (Starting with Pre-Test) A sphere has a radius of 4 in. Ray-Sphere Intersection with Simple Math. NOTE: This article is OLD! (From 2013!). Information in it may be out of date or outright useless, and I have no plans to update it. Beware! Lately I've been working on a ray tracer. It's been going well (or at least as well as I could hope my first renderer could go), but it has been a slow process. I don't have a formal math background - my day. Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It only takes a minute to sign up. Sign up to join this community . Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Home Public; Questions; Tags Users Unanswered Teams. Stack Overflow for Teams - Collaborate and.

- Beyond this, it is not only spheres which come in exotic versions. It is now known that 4-dimensional space itself (or R 4) comes in a variety of flavours. There is the usual flat space, but alongside it are the exotic R 4 s. Each of these is topologically identical to ordinary space, but not differentially so
- Sometimes it is more convenient to create sphere-like objects in terms of the spherical coordinate system. The following example application program will create two spheres. We need to add the Matrix3 and Point3 classes to the current project. And also add a new class, DrawSphere, to the project. Now we need to add a Spherical method to the Matrix3 class. The Matrix3 class has been discussed.
- sphere: (x-xc)^2+(y-yc)^2+(z-zc)^2 = R^2. Use the symmetric equation to find relationship between x and y, and x and z. Then plug in y and z in terms of x into the equation of the sphere. Then find x, and then you can find y and z. If x gives you an imaginary result, that means the line and the sphere doesn't intersect
- Math Biosci 58(1):129-139 Article Google Scholar Ridley JN (1986) Ideal phyllotaxis on general surfaces of revolution. Math Biosci 79(1):1-24 Article Google Scholar Saff EB, Kuijlaars ABJ (1997) Distributing many points on a sphere. Math Intell 19(1):5-1
- This MATLAB function returns the radar cross section pattern of a sphere of radius r as a function of signal frequency, fc, and signal propagation speed, c
- Properties of Sphere • The opposite sides of a rectangle are parallel. • A sphere is perfectly symmetrical • It is not a polyhedron • All points on the surface are the same distance r from the center • It has no side or corner • It has constant mean curvature • It has a constant width and.

Volume of the sphere = 4/3 × 3.14 × 27 Volume of the sphere = 4/3 × 84.78 Volume of the sphere = 4/3 × 84.78/1 Volume of the sphere = (4 × 84.78)/(3 × 1) Volume of the sphere = (339.12)/3 Volume of the sphere = 113.04 cm 3 Example #3 Find the volume of a sphere that has a radius of 2/3 cm Volume of the sphere = 4/3 × π × r The unit sphere \( S^2 \) in three dimensions is the set of all points \( x \) in \( R^3 \) at distance \( |x| = 1 \) from the origin. Here we are considering just the surface of the sphere, not its interior. In contrast to the circle, it is not possible to equally distribute points on the sphere except in a few special cases (the platonic solids illustrated below). Instead many different. Maths. 2D and 3D shapes. Duration 01:10. Description Classroom Ideas. Description. An introduction to the properties and uses of spheres and cubes. A sphere has no point, no edges and just one. Sphere vs Steradian. The surface area of a sphere is 4πr 2, The surface area of a steradian is just r 2. So a sphere measures 4π steradians, or about 12.57 steradians. Likewise a steradian is 1/12.57, or about 8% of a sphere. And because we measure an angle, it doesn't matter what size the sphere is, it will always measure 4π steradians Making Hemispheres out of Paper I'm a high school math teacher, and I've been trying to figure out how you would make a sphere from a piece of paper, for example, if I wanted my geometry students to take a piece of paper and fold/cut it so that it would fit perfectly over the northern hemisphere of a globe. I first decided that I would focus on how to get a piece of paper to fold into a.

The sphere packing problem is to find this highest proportion, also called the sphere packing constant. For an easier example, let's drop down a dimension: instead of packing spheres into 3D space let's pack discs into 2D space. In dimension two the best packing [comes from the] honeycomb, explains Viazovska. In a traditional honeycomb. A sphere is a three-dimensional solid consisting of all points that have the same distance from a given center C. This distance is called the radius r of the sphere. You can think of a sphere as a three-dimensional circle . Just like a circle, a sphere also has a diameter d, which is twice half the length of the radius, as well as chords and secants. In a previous section, you learned h

Volume of spheres (Worksheets) Surface area of spheres (Worksheets) Example: Calculate the volume of sphere with radius 4 cm. Solution: Volume of sphere. We can also change the subject of the formula to obtain the radius given the volume. Example: The volume of a spherical ball is 5,000 cm 3 Calculating a Sphere's Radius from Volume. By rearranging the formula for a sphere's volume, it is possible to find the radius of a sphere with a known volume. The following is the formula used to calculate the radius of a sphere: Again, the 3, 4, and pi are constants. The formula for a sphere's radius can be simplified using the. Maths in a minute: The Riemann sphere. Submitted by Marianne on October 1, 2013. If you walk around the two-dimensional plane you can keep walking indefinitely in all directions. You could say, in a very hand-wavy and intuitive sense, that there is infinity all around the edge of the plane, only of course you can never get to or see that edge

Vedic Maths was discovered by Shri Bharati Krishna Tirthaji during his extensive research on the Vedas. An avid reader and researcher by nature he went into deep meditations and studied the four Vedas extensively only to discover the sixteen sutras lying hidden in the verses of the Atharva Veda Math > Geometry > Surface Area > Spheres; Surface Area of Spheres and Hemispheres Worksheets. The total area that the surface of the sphere or hemisphere occupies is what grade 7, grade 8, and high school students are expected to determine in these printable worksheets. The sphere, with no flat surfaces has the formula 4πr 2. However, for the hemisphere, with a curved and a flat surface, we. Which solid figure describes a baseball? A sphere! Kids completing this third grade math worksheet match common objects to solid geometric figures. 3rd grade. Math. Worksheet. Spot the Spheres. Worksheet. Spot the Spheres . Spheres are all around us—basketballs, globes, even the planet Earth! Help your students develop an understanding of this 3-D shape by identifying spheres in pictures and. We explore how geometry on a sphere compares to traditional plane geometry. We present formulas and theorems about the 2-gon and the 3-gon in spherical geometry. We end with an alternative proof of Euler's Formula using spherical geometry. 1. Introduction. Euclid's fth postulate, the \parallel postulate, guarantees that there is one and only one line parallel to a given line l through a. arXiv.org > math > arXiv:1603.04246 Help | Advanced Search All fields Title Author Abstract Comments Journal reference ACM classification MSC classification Report number arXiv identifier DOI ORCID arXiv author ID Help pages Full tex

Sphere definition at Dictionary.com, a free online dictionary with pronunciation, synonyms and translation. Look it up now GeoGebra - Free Online Geometry Tool. Geogebra is the best online geometry software for creating different geometric figures - points, lines, angles, triangles, polygons, circles, elipses, 3D planes, pyramids, cones, spheres.... Please wait while loading (approx. 1-2 minutes). You can also draw graphs of functions Math Open Reference. Home Contact About Subject Index. Surface area of a sphere. Definition: The number of square units that will exactly cover the surface of a sphere. Try this Drag the orange dot to adjust the radius of the sphere and note how the area changes. The surface area of a sphere is given by the formula Where r is the radius of the sphere. In the figure above, drag the orange dot.