Understanding Electromagnetic Waves

AI Thread Summary
Light waves travel through mediums like the Earth's atmosphere by oscillating electric and magnetic fields, which are transverse waves. The intensity of light radiation emitted from a source, such as a light bulb, can be visualized as following a sine wave pattern, where the frequency determines the color of the light. While the atmosphere is mostly empty space, it still allows light waves to propagate, albeit with some scattering effects. Understanding the electromagnetic field's behavior in a medium can be aided by practical demonstrations, although clarity in presentation is essential for effective learning. Overall, grasping the nature of light waves involves recognizing their transverse characteristics and the role of frequency in determining light color.
FOIWATER
Gold Member
Messages
434
Reaction score
12
I am having trouble understanding how a light wave travels through a medium, such as the Earth's atmosphere when emitted from a light bulb...

I have read some topics on the difference between transverse and longitudinal waves, but I am having trouble understanding how they exist.

I can imagine radiation existing as being emitted from a source, in all directions, and the intensity of the radiation over time follows a sine wave, and the period of this sine wave determines the color of the light, IE, how often the radiation peaks and crests in intensity over time. That's kind of how I imagine it, but is it correct.
 
Engineering news on Phys.org
FOIWATER said:
I am having trouble understanding how a light wave travels through a medium, such as the Earth's atmosphere when emitted from a light bulb...

Can you be more specific, as our atmosphere is mostly empty space to visible light.

http://en.wikipedia.org/wiki/Speed_of_light#In_a_medium
 
empty space, than.
 
nsaspook said:
A simple device to detect the E field of a wave.


A very good demo but marred by the emphasis on practical details and an illegible white board diagram. They must have been very chuffed when they got it working and could 'feel' the wavefronts!
 
Last edited by a moderator:

Thread '3-terminal device external modeling'

Very basic question. Consider a 3-terminal device with terminals say A,B,C. Kirchhoff Current Law (KCL) and Kirchhoff Voltage Law (KVL) establish two relationships between the 3 currents entering the terminals and the 3 terminal's voltage pairs respectively. So we have 2 equations in 6 unknowns. To proceed further we need two more (independent) equations in order to solve the circuit the 3-terminal device is connected to (basically one treats such a device as an unbalanced two-port...
View full post »

Thread 'Two capacitors, etc.'

suppose you have two capacitors with a 0.1 Farad value and 12 VDC rating. label these as A and B. label the terminals of each as 1 and 2. you also have a voltmeter with a 40 volt linear range for DC. you also have a 9 volt DC power supply fed by mains. you charge each capacitor to 9 volts with terminal 1 being - (negative) and terminal 2 being + (positive). you connect the voltmeter to terminal A2 and to terminal B1. does it read any voltage? can - of one capacitor discharge + of the...
View full post »

Similar threads

Electromagnetic field vs electromagnetic wave "radiation"
Replies
7
Views
2K
Can a Square Wave Tachometer Drive be Powered by a Sine Waveform?
Replies
16
Views
3K
B Interpreting light as Maxwell's EM wave
2
Replies
65
Views
5K
I Do electromagnetic waves fade with distance in vacuum?
Replies
2
Views
1K
Calculating Electromagnetic Wave Intensity in a 30 sq m Room
Replies
3
Views
1K
EM Waves Generated by an LC Circuit?
Replies
30
Views
4K
Am vs Fm variable capacitor receiver, what is the difference?
Replies
2
Views
2K
I Are electromagnetic waves sine waves?
Replies
3
Views
3K
How Do I Generate Quarter Sine Waves?
Replies
8
Views
5K
I How to Measure the Energy of an Electromagnetic Wave?
Replies
4
Views
2K

Hot Threads

Recent Insights

Back
Top