Projected area is the two
dimensional
area
Area is the measure of a region's size on a surface. The area of a plane region or ''plane area'' refers to the area of a shape or planar lamina, while '' surface area'' refers to the area of an open surface or the boundary of a three-di ...
measurement of a three-dimensional object by projecting its shape on to an arbitrary plane. This is often used in
mechanical engineering
Mechanical engineering is the study of physical machines and mechanism (engineering), mechanisms that may involve force and movement. It is an engineering branch that combines engineering physics and engineering mathematics, mathematics principl ...
and
architectural engineering
Architectural engineering or architecture engineering, also known as building engineering, is a discipline that deals with the engineering and construction of buildings, such as environmental, structural, mechanical, electrical, computational, e ...
related fields, especially for
hardness
In materials science, hardness (antonym: softness) is a measure of the resistance to plastic deformation, such as an indentation (over an area) or a scratch (linear), induced mechanically either by Pressing (metalworking), pressing or abrasion ...
testing,
axial stress, wind pressures, and
terminal velocity
Terminal velocity is the maximum speed attainable by an object as it falls through a fluid (air is the most common example). It is reached when the sum of the drag force (''Fd'') and the buoyancy is equal to the downward force of gravity (''FG ...
.
The geometrical definition of a projected area is: "the rectilinear
parallel projection of a surface of any shape onto a plane". This translates into the equation:
where A is the original area, and
is the angle between the normal to the local plane and the line of sight to the surface A. For basic shapes the results are listed in the table below.
See also
*
Surface area
The surface area (symbol ''A'') of a solid object is a measure of the total area that the surface of the object occupies. The mathematical definition of surface area in the presence of curved surfaces is considerably more involved than the d ...
References
Engineering concepts
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