Everything about Nichols Radiometer totally explained
A
Nichols radiometer is the apparatus used by Nichols and Hull in
1901 for the measurement of
radiation pressure. It consisted of a pair of small silvered glass
mirrors suspended in the manner of a
torsion balance by a fine
quartz fibre within an enclosure in which the air pressure could be regulated. The torsion head to which the fiber was attached could be turned from the outside by means of a
magnet. A beam of
light was directed first on one mirror and then on the other, and the opposite deflections observed with mirror and scale. By turning the mirror system around so as to receive the light on the unsilvered side, the influence of the air in the enclosure could be ascertained. This influence was found to be a minimum, and to have an almost negligible value, at an air pressure of about 16
mmHg (2.1
kPa). The radiant energy of the incident beam was deduced from its heating effect upon a small blackened silver disk, which was found to be more reliable than the
bolometer when it was first used. With this apparatus the experimenters were able to obtain an agreement between observed and computed radiation pressures within about 0.6 %. The original apparatus is at the
Smithsonian Institution.
This apparatus is sometimes confused with the
Crookes radiometer in which vanes turn in a partial vacuum under the influence of low pressure gas molecules and not directly by the photons themselves.
Further Information
Get more info on 'Nichols Radiometer'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://nichols_radiometer.totallyexplained.com">Nichols radiometer Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |
