Tagged Questions
2
votes
3answers
76 views
Producing electricity from all wavelengths of electromagnetic spectrum
Is it possible to produce electricity from all wavelengths of electromagnetic spectrum beside visible light ?Like using gamma rays or x-rays .
3
votes
1answer
83 views
Why does electromagnetic waves travel slower in well isolated conductor?
Wikipedia writes, that
Propagation speed is affected by insulation, so that in an unshielded copper conductor ranges 95 to 97% that of the speed of light, while in a typical coaxial cable it is ...
0
votes
0answers
86 views
what exactly do electric waves transfer from one point of the wire to other..? [duplicate]
Possible Duplicate:
how does electricity propagate in a conductor?
so basically i was considering the speed of the charges inside wire defined by the drift velocity and speed of electric ...
0
votes
0answers
59 views
MIT's 230% efficient LEDs. A reprise about cooling
This is a reprise of the question Can someone explain the science behind MIT's 230% efficient LEDs?
The PRL paper doesn't detail what the efficiency of heat-to-light energy conversion is, which in ...
1
vote
2answers
1k views
Microwaves vs Gas or Electric Coil heating of a water boiler in a typical household
Wouldn't it be more energy efficient and or safe to use microwaves to heat our home's water boiler instead of using dangerous gas or hot electric coils that could catch other things on fire? I'm kinda ...
11
votes
6answers
2k views
Why is electricity not transmitted wirelessly?
Why is electricity not transmitted wirelessly such that we don't need to span cables on the earth's surface? As in: electricity is transmitted wirelessly from the power plant to the household.
6
votes
1answer
608 views
What’s the relationship between thermal radiation and Johnson thermal noise?
All objects above absolute zero emit radiation due to random collisions between the atoms they are made of. The spectrum of radiation emitted varies according to the temperature of the object, I ...
