Why is using visible light for radio transmission not feasible?

AI Thread Summary
Using visible light for radio transmission is impractical due to its short wavelength, which limits its ability to diffract around obstacles, requiring a clear line of sight for communication. While devices like TV remotes and infrared communication ports utilize visible or infrared light for data transmission, they are not effective for long-distance radio-like transmissions. The principle of long-distance transmission is feasible, as evidenced by detecting AM visible light signals from pulsars. However, the rapid attenuation of visible light signals in obstructed environments poses significant challenges. Overall, effective communication using visible light necessitates unobstructed paths between devices.
bsmith
Messages
3
Reaction score
0

Homework Statement



Why can't you make radio transmitter that transmits visible light instead in the same way we transmith AM signals?

Homework Equations





The Attempt at a Solution



Im thinking maybe they would not be very effective as their wavelenth is so small, they would die out rapidly...
 
Physics news on Phys.org
There are lots of practical devices that use AM visible or infra red light for data transmission. For example TV remote controls, infrared communications ports on PCs, etc.

There is no problem in principle with long distance transmission. For example we can detect the AM visible light signals from pulsars many light years away from earth. However short wavelengths do not diffract round large objects, so you can only communicate between devices that can "see" each other with no obstructions in between them.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top