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At first, let us define an angle in radians:
Consider an arc of lenght L over an angle alfa in a circle with radius R. The angle alfa is defined as alfa=L/R [in radians]. Similarly, an stereo angle is defined in a sphere with radius R over an area S, and the stereo angle alfa is defined as: alfa=S/R^2 [in steradians]. The sphere has S=4.pi.R^2, so the corresponding angle of the sphere in steradians is
alfa=S/R^2
alfa=4.pi.R^2/R^2
alfa=4.pi [steradians]
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How many faces on a sphere?
none
A sphere has how many faces and how many corners?
A sphere has no faces an corners. The term "faces" and "corners" are applied to polyhedrons, figures with flat surfaces.
How many corners faces and edges does a sphere have?
A sphere has no edges, because an edge is defined as where two faces meet. Likewise, it has no faces, because a face is defined as the flat surface of an object. Likewise, it has no corners either.
Find the surface area of a sphere of radius 10.5cm?
The surface area is 1,385.4 cm2
A solid round figure?
A sphere. In Geometry, it is a round solid figure. Every point on it's surface is an equal distant from it's center.
How many solid degrees are there in a sphere?
Spheres are measured with solid angles (which are like two dimensional angles). These angles can be measure with square degrees or steradians. A sphere measures 129300/π square degrees (or about 41,253 square degrees). A sphere measures 4π steradians (or about 12.566 steradians.)
How many steradians in a hemisphere?
There are 2*pi stradians or tau steradians in a hemisphere.
What are properties of angles?
They are measures of angular displacement. In two dimensional space they may be measured in degrees (by beginners) or in radians. There are 2*pi radians in a revolution. In 3-d space angles are measured in steradians. A sphere measures 4*pi steradians
What directions light travel?
Light travels coincentrically in a sphere from it's source (2-pi steradians solid angle.) That is why light from a candle will shine in all directions.
What direction does light travel?
Light travels coincentrically in a sphere from it's source (2-pi steradians solid angle.) That is why light from a candle will shine in all directions.
How many degrees are there in a hemisphere?
hemispheres and deg (degrees) are not compatible. solid angles are measured in steradians of spheres 2pi steradians or 0.5 spheres in a hemisphere In cartography, a hemisphere would encompass 180 degrees of longitude.
Different systems of measuring an angle?
There are three main units for measuring a plane angle. The most important, in advanced mathematics, is the radian. there are 2pi radians in a whole turn - or in a circle. A better known measure, because it is taught in elementary mathematics, is the degree which is equivalent to 1/360 of a turn. Finally, there is the gradian [1/400 of a turn], which is rarely used. In 3-dimensional space, angles are measured in steradians and there are 4pi steradians in a sphere.
How many syablles in word sphere?
Sphere is one syllable: sphere.
How many edge in sphere?
There is no edge in a SPHERE
What angle is a cube?
The measure of the angle of a cube is pi/2 steradians.
How many corners on a sphere?
There are no corners to a sphere because a sphere should have no vertices.
How many radii a sphere have?
There are infinite radii in a sphere.
