The Naked Scientists
  • Login
  • Register
  • Podcasts
      • The Naked Scientists
      • eLife
      • Naked Genetics
      • Naked Astronomy
      • In short
      • Naked Neuroscience
      • Ask! The Naked Scientists
      • Question of the Week
      • Archive
      • Video
      • SUBSCRIBE to our Podcasts
  • Articles
      • Science News
      • Features
      • Interviews
      • Answers to Science Questions
  • Get Naked
      • Donate
      • Do an Experiment
      • Science Forum
      • Ask a Question
  • About
      • Meet the team
      • Our Sponsors
      • Site Map
      • Contact us

User menu

  • Login
  • Register
  • Home
  • Help
  • Search
  • Tags
  • Member Map
  • Recent Topics
  • Login
  • Register
  1. Naked Science Forum
  2. Non Life Sciences
  3. Physics, Astronomy & Cosmology
  4. How is photon number related to wattage of a solar panel?
« previous next »
  • Print
Pages: 1 [2]   Go Down

How is photon number related to wattage of a solar panel?

  • 27 Replies
  • 12454 Views
  • 0 Tags

0 Members and 1 Guest are viewing this topic.

Offline syhprum

  • Naked Science Forum King!
  • ******
  • 5065
  • Activity:
    8.5%
  • Thanked: 64 times
    • View Profile
How is photon number related to wattage of a solar panel?
« Reply #20 on: 06/12/2011 12:03:29 »
is a Barn-yard the imperial measure of nuclear cross sectional area i.e one Barn yard equals 0.8359 * 10^-28 square meter
Logged
syhprum
 



Offline Soul Surfer

  • Naked Science Forum King!
  • ******
  • 3384
  • Activity:
    0%
  • Thanked: 6 times
  • keep banging the rocks together
    • View Profile
    • ian kimber's web workspace
How is photon number related to wattage of a solar panel?
« Reply #21 on: 06/12/2011 17:56:48 »
Going back into ancient history the barn (note no yard)  is another good example of humour on science when the the first scientists doing nuclear science needed a measure for the sort of target that an atomic nucleus presented.  Now a big nucleus is about 10^-14 meters across and so its cross sectional area is about 10^-28  sq metres  when they first realised that that was the size of their target someone said its as big as a barn door (from the saying that its poor shooter that couldn't hit a barn door) and the name stuck.   There are a whole load of other target sizes for lower probability events see  http://en.wikipedia.org/wiki/Barn_(unit)

I have also just done a search on another interesting but old unit  the "hide"  which is the area of land needed to completely support an extended family unit  and is around 30-120 acres.  This could come into modern units on population and self sufficiency.
Logged
Learn, create, test and tell
evolution rules in all things
God says so!
 

Offline syhprum

  • Naked Science Forum King!
  • ******
  • 5065
  • Activity:
    8.5%
  • Thanked: 64 times
    • View Profile
How is photon number related to wattage of a solar panel?
« Reply #22 on: 09/12/2011 10:51:14 »
I know the barn is not a S.I unit but it is tolerated but in a recent Phsyorg article I was reading a milli-barn was quoted as being 10^-27 cm^2 which I think is stretching our toleration a bit far
« Last Edit: 09/12/2011 10:52:45 by syhprum »
Logged
syhprum
 

Marked as best answer by on 20/01/2021 04:56:41

Offline Bored chemist

  • Naked Science Forum GOD!
  • *******
  • 21297
  • Activity:
    100%
  • Thanked: 485 times
    • View Profile
  • Undo Best Answer
  • How is photon number related to wattage of a solar panel?
    « Reply #23 on: 09/12/2011 18:23:14 »
    The barn yard atmosphere is a unit of energy (a rather small one).
    An area  multiplied by a distance gives a volume, and a volume multiplied by a pressure gives energy.
    BTW if you don't like the "milli barn" as a unit for capture cross section you would really hate the alternative. Cross sections for improbable events are sometimes quoted in sheds.
    Logged
    Please disregard all previous signatures.
     

    Offline damocles

    • Hero Member
    • *****
    • 756
    • Activity:
      0%
    • Thanked: 1 times
      • View Profile
    How is photon number related to wattage of a solar panel?
    « Reply #24 on: 09/12/2011 20:30:31 »
    There is actually a perfectly convenient and respectable SI alternative to millibarn.

    1 barn = 1.E-28 m2, therefore 1 millibarn = 1.E-31 m2

    1 fm = 1.E-15 m, therefore 1 fm2 = 1.E-30 m2 = 10 millibarn
    Logged
    1 4 6 4 1
    4 4 9 4 4     
    a perfect perfect square square
    6 9 6 9 6
    4 4 9 4 4
    1 4 6 4 1
     



    Offline Geezer

    • Naked Science Forum King!
    • ******
    • 8314
    • Activity:
      0%
    • Thanked: 7 times
    • "Vive la résistance!"
      • View Profile
    How is photon number related to wattage of a solar panel?
    « Reply #25 on: 10/12/2011 08:57:22 »
    Quote from: damocles on 09/12/2011 20:30:31
    There is actually a perfectly convenient and respectable SI alternative to millibarn.

    1 barn = 1.E-28 m2, therefore 1 millibarn = 1.E-31 m2

    1 fm = 1.E-15 m, therefore 1 fm2 = 1.E-30 m2 = 10 millibarn

    Yes, but how many sheepies would that hold?
    Logged
    There ain'ta no sanity clause, and there ain'ta no centrifugal force æther.
     

    Offline damocles

    • Hero Member
    • *****
    • 756
    • Activity:
      0%
    • Thanked: 1 times
      • View Profile
    How is photon number related to wattage of a solar panel?
    « Reply #26 on: 10/12/2011 13:55:25 »
    Quote from: Geezer on 10/12/2011 08:57:22
    Quote from: damocles on 09/12/2011 20:30:31
    There is actually a perfectly convenient and respectable SI alternative to millibarn.

    1 barn = 1.E-28 m2, therefore 1 millibarn = 1.E-31 m2

    1 fm = 1.E-15 m, therefore 1 fm2 = 1.E-30 m2 = 10 millibarn




    Yes, but how many sheepies would that hold?

    approximately 0.314 attosheep
    Logged
    1 4 6 4 1
    4 4 9 4 4     
    a perfect perfect square square
    6 9 6 9 6
    4 4 9 4 4
    1 4 6 4 1
     

    Offline acsinuk

    • Sr. Member
    • ****
    • 422
    • Activity:
      9.5%
    • Thanked: 6 times
      • View Profile
      • electricmagnofluxuniverse.blogspot.com
    How is photon number related to wattage of a solar panel?
    « Reply #27 on: 11/12/2011 02:59:49 »
    Have just looked up Oliver Boyd and found that a 1 kWh is equivalent to 2.247 * 10^25 electron-volts which means that as average light photons have 1.1 eV each then 2*10^25 is good aproximation for a one square metre PV panel which gets 1 kW peak at noon on equator after allowing for third haze reduction. The power is received per square metre but to change it into energy we must multipy by time.  So each photon is not a magic massless ray but a volume of 3 dimensional magnetic flux energy which is absorbed at the surface of the PV cell.
    CliveS
    Logged
    A.C.Stevens
     



    • Print
    Pages: 1 [2]   Go Up
    « previous next »
    Tags:
     

    Similar topics (5)

    Is there a "photon boundary"?

    Started by GeezerBoard Physics, Astronomy & Cosmology

    Replies: 14
    Views: 7221
    Last post 22/09/2010 11:40:15
    by yor_on
    Will a photon clock run at a different rate from an atomic clock under gravity?

    Started by amritBoard Physics, Astronomy & Cosmology

    Replies: 147
    Views: 67970
    Last post 07/06/2010 06:43:34
    by Geezer
    Two low energy photons for one high energy photon in fluorescence possible?

    Started by McKayBoard Physics, Astronomy & Cosmology

    Replies: 6
    Views: 3176
    Last post 19/05/2019 13:05:28
    by alancalverd
    Because we have no dark matter planet in our solar system, can we assume that dark matter is not sticking to itself?

    Started by thedocBoard Physics, Astronomy & Cosmology

    Replies: 3
    Views: 3291
    Last post 18/08/2016 02:39:19
    by PmbPhy
    Is solar energy the same as light energy?

    Started by FeliciaBoard Technology

    Replies: 6
    Views: 19363
    Last post 19/03/2020 15:17:27
    by Paul25
    There was an error while thanking
    Thanking...
    • SMF 2.0.15 | SMF © 2017, Simple Machines
      Privacy Policy
      SMFAds for Free Forums
    • Naked Science Forum ©

    Page created in 0.13 seconds with 54 queries.

    • Podcasts
    • Articles
    • Get Naked
    • About
    • Contact us
    • Advertise
    • Privacy Policy
    • Subscribe to newsletter
    • We love feedback

    Follow us

    cambridge_logo_footer.png

    ©The Naked Scientists® 2000–2017 | The Naked Scientists® and Naked Science® are registered trademarks created by Dr Chris Smith. Information presented on this website is the opinion of the individual contributors and does not reflect the general views of the administrators, editors, moderators, sponsors, Cambridge University or the public at large.