Ne W2
1 0 KI. Calculate the luminous inten
Uislunce of the
luminous intensity and the
[HSEB 20651
U
total luminous flux from the sun
Solution:
Here, illuminance (I) = 1.5 x 10° lumen/m²,
Distance (T) = 1.5 x 10 km =1.5 x 108 m
Let L be the luminous intensity of the sun, then
or, L= TXT =1.5 x 10°x (1.5 x 108)2
= 3.375 x 102 cd.
Total luminous flux from the sun = 410 I
= 41 x 3.375 x 1021 = 4.24 x 1022 /m
Example 3. If a source has luminous intensity of 400 cd, (a) how much
luminous flux is emitted by the source? (b) what is the illuminance at a point
on the table which is 1.6 m directly below the source?
Solution:
Here, Luminous intensity (L) = 400 cd
Answers: 1
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Ne W2
1 0 KI. Calculate the luminous inten
Uislunce of the
luminous intensity and the...
1 0 KI. Calculate the luminous inten
Uislunce of the
luminous intensity and the...
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