Mensuration for a Cube of diagonal 271.932 units: Volume, Surface Area, Diagonal and Circumradius



You are given a cube of diagonal 271.932 units. 
So we may compute that the side = diagonal/√3 = 157 units.

Computing the Total Surface Area, Volume and Diagonal of the cube


Side (or length) of the cube = 157 units. 
Total Surface area of the cube = 4 * side2 = 4 * 157 * 157 = 98596 square units.
Volume of the cube = side3 = 157 * 157 * 157 = 3869893 cubic units. 
Length of the diagonal of the cube = (3 * side2)0.5 = 271.93 units  (Extending the Pythagorean theorem to three dimensions)

You might also make these calculations by considering the cube to be a special case of other 3D hexahedrons: an equilateral cuboid or a regular square prism or a square parallelopiped. 

Circumsphere of the Cube

A sphere touching all six vertices of a cube is known as its circumsphere. 
The circumsphere of this cube as a radius equal to (length of the diagonal)/2 = 135.97


Now, if we know that the cube is made of Aluminum and we measure the side in inches and the density of the material is 0.258 pounds per cubic inch, we can calculate the mass of the cube:
Mass of the cube = Density x Volume = 998432.39 pounds. 
All cubes are geometrically similar. 

Let's compare this current cube (let's call it cube A) with a cube B of side 1 units
The scale factor A : B = 157:1
Ratio of surface areas of A : B  = 98596: 1 = 24649 : 1 (this holds true whether you compare total surface area or surface area per side, or any corresponding pairs of surface areas between the cubes)
Ratio of volumes of A:B = 3869893 : 1 = 3869893 : 1

While working with scale factors, square the scale factor and multiply it by the area of the original figure to determine the area of the new figure.
Similarly the ratio of volumes will be the cube of the scale factor - as you're multiplying the scale factor thrice.

What if the current cube is made hollow with a thickness of 2 units?

In that case, the volume of the cubic gap inside the current cube has a size of 155 units. So the volume of the cubic gaps is 155 * 155 * 155 cubic units = 3723875 cubic units.
So the volume of the material used to construct the cube = Volume of the outer cube - volume of the gap = 3869893 - 3723875 = 146018 cubic units.


You may find some more useful notes and information about the cube over here.


Some more example(s):


Geometric Properties of a cube which is of larger size: Properties like Surface Area, Volume, Circumradius, Circumsphere, Mensuration etc.



To understand more about the geometric features and properties of cubes, formulas related to mensuration and the principles of cubical or octahedral symmetry - you might find it useful to read the properties of a Cube tutorial over here. Many of these concepts are a part of the Grade 9 and 10 Mathematics syllabus of the UK GCSE curriculum, Common Core Standards in the US, ICSE/CBSE/SSC syllabus in India. You may check out our free and printable worksheets for Common Core and GCSE.
 


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