× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
5
o
5
4
m
4
b
4
x
4
a
4
l
4
t
4
S
4
m
3
s
3
New Topic  
oemBiology oemBiology
wrote...
Posts: 1245
5 years ago Edited: 5 years ago, oem7110
Viewpoint 1
"DISCOVERY OF INFRARED

In 1800, William Herschel conducted an experiment measuring the difference in temperature between the colors in the visible spectrum. He placed thermometers within each color of the visible spectrum. The results showed an increase in temperature from blue to red. When he noticed an even warmer temperature measurement just beyond the red end of the visible spectrum, Herschel had discovered infrared light!"



Viewpoint 2
According to Plank's quantum theory, energy associated with a photon is
 E=hf, where f is the frequency.
But f=c/λ, where λ is the wavelength
So, E=hc/λ,  as energy of photon and wavelength follows inverse proportion ( i.e. If energy increases the wavelength decreases )

Question
Blue has more energy than Red, but why Red can rise temperature higher than Blue?

Does anyone have any suggestions?
Thanks in advance for any suggestions


https://science.nasa.gov/ems/07_infraredwaves
Read 261 times
5 Replies

Related Topics

Replies
wrote...
Valued Member
Educator
5 years ago
These findings are based on Herschel's experiment that's explained here:

http://www.ipac.caltech.edu/outreach/Edu/Herschel/backyard.html

The main reason is due to the fact that the prism refracts light in such a way that the "blue" part is more spread than "red" part. So that overall the energy hitting the thermometer is greater in the infrared and red part than on the blue part of the spectrum.
oemBiology Author
wrote...
5 years ago Edited: 5 years ago, oem7110
Thank you very much for suggestions (^v^)
Post Merge: 5 years ago

"Why the ocean is blue

Lakes and oceans appear blue for several reasons. One is that the surface of the water reflects the color of the sky.

When materials absorb light, the light's energy is transferred to the material, often as heat. Some of the light hitting the surface is reflected back directly but most of it penetrates the surface, interacting with its molecules. The water molecule can vibrate in three different modes when light hits it. The red, orange, yellow, and green wavelengths of light are absorbed and the remaining light we see is composed of the shorter wavelength blues and violets. This is the main reason why the ocean is blue."
http://www.pindex.com/b/teresa-mcalear/stuff


The above statement seems contradiction with your below statement, if blue is more spread than red, so blue must be less and less under the ocean, but ocean is blue.

"the "blue" part is more spread than "red" part. So that overall the energy hitting the thermometer is greater in the infrared and red part than on the blue part of the spectrum."

Do you have any suggestions?
Thank you very much for any suggestions (^v^)

wrote...
Valued Member
Educator
5 years ago Edited: 5 years ago, bio_man
Keep in mind oem7110 that the ocean isn't put water. Try this experiment using a bucket of water and you'll get more consistent results.
oemBiology Author
wrote...
5 years ago Edited: 5 years ago, oem7110
I think this light issue is still unknown and also not confirmed under QM as well.

"The main reason is due to the fact that the prism refracts light in such a way that the "blue" part is more spread than "red" part. So that overall the energy hitting the thermometer is greater in the infrared and red part than on the blue part of the spectrum."  That is a very good answer for my original question.

Thank you very much for suggestions (^v^)
wrote...
Valued Member
Educator
5 years ago Edited: 5 years ago, bio_man
Keep in mind oem7110 that the ocean isn't put water. Try this experiment using a bucket of water and you'll get more consistent results.

* I was just suggesting that there are impurities in sea water that should also be considered.

Anyway, each individual blue photon is higher energy than a red photon, but the distribution of intensity in sunlight (or any source) is not equal for all wavelengths.

Look at this graph



It displays the wave concentration as wavelength increases, i.e. going from blue to red. Blue photons of light have lesser wavelength and can penetrate more than red, but there's a high concentration of red. This doesn't contradict the ocean question.
New Topic      
Explore
Post your homework questions and get free online help from our incredible volunteers
  1109 People Browsing
Related Images
  
 1023
  
 859
  
 231
Your Opinion
Who's your favorite biologist?
Votes: 585