- the unit,
steradian, sr = rad2.
Because the
surface area A of a
sphere is 4πr2, the
definition implies that a
sphere subtends 4π
steradians (≈ 12.56637 sr)...
-
solid angle of the Sun is 6.794×10−5
steradians and the
average solid angle of the Moon is 6.418×10−5
steradians. In
terms of the
total celestial sphere...
- as
equivalent to one candela-
steradian (symbol cd·sr): 1 lm = 1 cd·sr. A full
sphere has a
solid angle of 4π
steradians (≈ 12.56637 sr), so an isotropic...
-
Latin spatium ("space"), is a unit of
solid angle. 1 spat is
equal to 4π
steradians or
approximately 41253
square degrees of
solid angle (sequence A125560...
- 1700 lumens; if that
light is
radiated equally in all
directions (i.e. over 4π
steradians), it will have an
intensity of I V = 1700 lm 4 π sr ≈ 135 lm / sr...
-
constellations is the
total solid angle of the sky,
which is
exactly 4π
steradians, or 4π × (180/π)2 = 129,600/π
square degrees, or
approximately 41,252...
- of a
platonic solid is
equal to the
solid angle of a full
sphere (4π
steradians)
divided by the
number of faces. This is
equal to the
angular deficiency...
-
factor π {\displaystyle \pi } (which
really should have the
units of
steradians) is a
result of the fact that
intensity is
defined to
exclude the effect...
-
radiant intensity is the watt per
steradian (W/sr),
while that of
spectral intensity in
frequency is the watt per
steradian per
hertz (W·sr−1·Hz−1) and that...
- directions, the
total radiant flux
would be
about 18.40 mW,
since there are 4π
steradians in a sphere. A
typical modern candle produces very
roughly one candela...
