Infrared Remote Controls & Red Light: How Fast Does It Need To Go?

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SUMMARY

The discussion centers on the Doppler effect as it relates to infrared remote controls and the visibility of light. It concludes that even with extreme speeds, such as those produced by a mechanized launching apparatus like a rail-gun, the Doppler shift would not be sufficient to make infrared light visible. The conversation humorously highlights the impracticality of achieving this with a standard remote control, emphasizing that sound is a more accessible application of the Doppler effect than light.

PREREQUISITES
  • Understanding of the Doppler effect
  • Basic knowledge of electromagnetic waves
  • Familiarity with infrared light properties
  • Awareness of current technology limitations in light manipulation
NEXT STEPS
  • Research the principles of the Doppler effect in both sound and light
  • Explore advanced technologies like rail-guns and their applications
  • Investigate the visibility spectrum of light, particularly infrared
  • Study the physics of electromagnetic waves and their behavior at high velocities
USEFUL FOR

Physics enthusiasts, engineers, and anyone interested in the practical applications of the Doppler effect in light and sound.

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What happens if an infrared remote control is pointing and coming at your eye really fast while transmitting... would the frequency of the em waves increase? If so, how fast would it need to be traveling in order to appear red?
 
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How angry is the boyfriend/girlfriend that is hurling the remote control at your face?
 
Seriously though, the angriest of all angriest boyfiends/girlfriends could not cause enough Doppler shift to cause the infrared light to appear visible simply by hurling it at your face, without some sort of mechanized launching apparatus such as a highly sophisticated rail-gun or some such, which is beyond our present technology. On the other hand, a very angry boyfiend/girlfriend, might be able to hurl a well aimed remote control at your head such that you see red after the fact.
 
collinsmark said:
Seriously though, the angriest of all angriest boyfiends/girlfriends could not cause enough Doppler shift to cause the infrared light to appear visible simply by hurling it at your face, without some sort of mechanized launching apparatus such as a highly sophisticated rail-gun or some such, which is beyond our present technology.
Hey! I wanted to make a Doppler roller-coaster, with humans having enough speed to see the same colors through all the trip while the light itself did change.

Anyway, the easiest way to use Doppler's is for sound, not light. If you research enough the topic of light you could end up getting a Nobel or banned from PF :smile:
 
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