Ellipsoid Meaning

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In geometry when we are to define an Ellipsoid, we say that it is a closed surface whose all plane cross-sections are either ellipses or circles. An ellipsoid is symmetrical at around three mutually perpendicular axes which bisect at the centre. The surface area of the ellipsoid, as well as the Ellipsoid Volume, can also be calculated using the online calculator available at Vedantu. It is a free online tool that displays the surface area and volume of ellipsoid for the given radii.

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Ellipsoid Equation

If two axes are in equivalence, say m = n, and different from the 3rd i.e., o, then the ellipsoid is said to be an ellipsoid of revolution or spheroid. The ellipsoid shape formed is by revolving an ellipse around one of its axes. If m and n are greater than o, the spheroid will be oblate; if lesser, the surface will be a prolate spheroid. Having said that, If m, n and o are the principal semiaxes, a standard equation of such an ellipsoid is x²/m² + y²/n² + z²/o² = 1. A unique case occurs when m = n = o: then the surface is a sphere, and the bisection with any plane crossing through it is a circle.

Volume of an Ellipsoid Formula

An ellipsoid is a closed quadric surface which is a 3-D analogue of an ellipse. The standard equation of momental ellipsoid centered at the origin of a Cartesian coordinate plane. The spectral theorem can again be used in order to acquire a standard equation akin to the explanation given above.

The Ellipsoid volume formula is given below:

V = 4/3 π m n o

or the formula can also be written as:

V = 4/3 π r1 r2 r3


M = r1 = Radius of the axis 1 of the ellipsoid

N = r2 = Radius of the axis 2 of the ellipsoid

O = r3 = Radius of the axis 3 of the ellipsoid

Solved Examples on Volume of an Ellipsoid


The Ellipsoid Which Has a Radii are Given as M = 12 cm, N = 9 cm and o = 4 cm. Find the Volume of an Ellipsoid.



Radius (a) = 12 cm

Radius (b) = 9 cm

Radius (c) = 4 cm

Using the formula: V = 4/3 π a b c

V = 4/3 × 3.14 × 12 × 9 × 4

V = 1808.64 cm3


Evaluate the Volume of the Ellipsoid Whose Radii are 8 cm, 5 cm and 2 cm.



m = 8 cm

n = 5 cm

o = 2 cm

We are aware that the volume of the ellipsoid is (4/3) π m n o cubic units

Now, plug the values into the formula, we obtain

V = (4/3) π (8)(5)(2) cubic units

V = (4/3) 3.14* (8)(5)(2)

V = 334.94 cm3.

Fun Facts

  • Ellipse, a closed curve, the bisection of a right circular cone and a plane which is not parallel to the base, the axis, or an element of the cone.

  • Another definition of an ellipsoid is that it is the locus of points for which the sum of their distances from two the foci (fixed points) is constant.

  • Ellipsoid can be defined as the path of a point moving in a plane in such a way that the ratio of its distances from the focus (certain point) and the directrix(fixed straight line) is a constant lesser than one.

  • Any such path consists of this same property in terms of the 2nd fixed point and a 2nd fixed line, and ellipses often are considered as having two foci and two directrixes.

  • The proportion of distances, termed as the eccentricity, is the discriminant (q.v.; of a general equation that denotes all the conic sections.

  • The shorter the distance between the foci, the lesser is the eccentricity and the more closely the ellipse represents a circle.

  • Isaac Newton anticipated that due to the Earth’s rotation, the shape of its axis must be an ellipsoid instead of spherical, and cautious measurements confirmed his anticipation.

  • With increased appropriacy in measurements became possible, further deviations from the elliptical shape were discovered. 

FAQ (Frequently Asked Questions)

1. What is an Oblate Ellipsoid?

Answer: You know what an ellipsoid is? Now let’s see what an oblate ellipsoid is. An oblate ellipsoid shape also known as an oblate spheroid is formed by revolving an ellipse about its minor axis; and a prolate, about its major axis. In either instance, bisections of the surface by planes parallel to the axis of revolution are ellipses, while bisections by planes perpendicular to that axis are circles.

2. What is the Other Name of the Ellipsoid?

Answer: Often an ellipsoid of revolution (known as the reference ellipsoid) is typically used to resemble the Earth in geodetic calculations since such computations are simpler than those with more complex mathematical models. For such an ellipsoid, the difference between the polar radius and the equatorial radius (the semi-minor and semi-major axes, respectively) is about 21 km (13 miles), and the flattening is approximately 1 part in 300.

3. What is the Ellipsoid Volume?

Answer: In Mathematics, you already know that an ellipsoid is a surface that is obtained from the shape “sphere” by deforming it with respect to directional scalings. This is to say, an ellipsoid is a squashed sphere. The 3 pairwise perpendicular axes of symmetry bisect at the centre of symmetry which is termed as the centre of the ellipsoid. If the two axes consist of the same symmetry, then the ellipsoid is known to be the spheroid. If m, n and o are the radii, then the volume of the ellipsoid formula is given the following way:

The volume of the ellipsoid, = V = (4/3)πmno cubic units.