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Old October 3rd 06, 09:33 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,951
Default Where Does the Power Go?

Hi All,

Even armed with college texts on optics, Cecil hasn't got a whisper of
a chance in actually answering a direct question such as has been
posed below. A Xerox is not, after all, a calculator (nor does it
impart knowledge). As such, I will offer direct answers and let it go
at that.

On Tue, 03 Oct 2006 12:03:34 -0700, Richard Clark
wrote:

There is a common bare light bulb 1 meter away;
it illuminates a cm² target with 3µW @ 55nM of POWER;

what is:
the number of candela per steradians,
at the target,
from total bandwidth radiation?


5

or:
How much power is being supplied to the bulb?


100W

Can you see this amount of light on the target?


Depending upon the infirmities claimed: none to some.

Aside: only 0.7% as bright as the sun, in the tropics, at noon, on an
equinox.

73's
Richard Clark, KB7QHC