2 Q's: EM radiation produced by positive charge

In summary, the electric field moves along with the charge, and the magnitude may increase and decrease with time, and it may change direction.
  • #1
abro
20
0
I have 2 questions about EM radiation produced by an occilating electric charge.
Q1: With graphs of electromagnetic fields, you can see that it contains an electric and magnetic component. What does these mean or give information about?
Q2: By occilating the charge, you will get such a graph. How will it look like?

I have tried drawing, doing research on the Poyting vector and I keep finding that the magnetic field will be in the opposite direction on the graph, in the case of the positive charge. And I sure know how to find the direction of a magnetic field...
 

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  • #2
Q1. these graphs give information about the electric and magnetic fields... what don't you understand?
Q2. How the graph looks depends on how you oscillate the charge ... if you oscilate the charge sinusoidally, for example, you will get sinusoidal graphs.
See: http://www.cco.caltech.edu/~phys1/java/phys1/MovingCharge/MovingCharge.html

You are given a position-time graph for the charge; what does the acceleration-time graph look like?
 
  • #3
Simon Bridge said:
Q1. these graphs give information about the electric and magnetic fields... what don't you understand?
Q2. How the graph looks depends on how you oscillate the charge ... if you oscilate the charge sinusoidally, for example, you will get sinusoidal graphs.
See: http://www.cco.caltech.edu/~phys1/java/phys1/MovingCharge/MovingCharge.html

You are given a position-time graph for the charge; what does the acceleration-time graph look like?

With the picture I attached, you can find the EM graph aswell. What I don't understand about that graph is wether it's the direction or magnitude of the the field. I have tried understanding what the graph of a charge moving sinusoidally look like, but it's inconsistent with for example the Poyting vector.
 
  • #4
The example EM graph on what you supplied shows both the magnitude (the line) and the direction (the arrow). That is why the E and the B curves are drawn perpendicular to each other.

The graph of the sinusoidally moving charge is given to you in thr same picture - top right - as y vs t. This is a position-time graph. There is nothing wrong with it.
 
  • #5
Simon Bridge said:
The example EM graph on what you supplied shows both the magnitude (the line) and the direction (the arrow). That is why the E and the B curves are drawn perpendicular to each other.

The graph of the sinusoidally moving charge is given to you in thr same picture - top right - as y vs t. This is a position-time graph. There is nothing wrong with it.

So when the charge moves up, the electric field moves up?
The magnetic field move in a circle when it moves up, but it's in the other direction when moving up, that's the problem I run into.
 
  • #6
The electric field moves along, not up and down.
The magnitude may increase and decrease with time, and it may change direction.

How is the electric field related to the motion of the charge?
Don't guess - if you don;t know, look it up. I gave you a link even.
 
  • #7
Simon Bridge said:
The electric field moves along, not up and down.
The magnitude may increase and decrease with time, and it may change direction.

How is the electric field related to the motion of the charge?
Don't guess - if you don;t know, look it up. I gave you a link even.

Took me some time to get the applet running, but now I can grasp it. Thanks!
 

FAQ: 2 Q's: EM radiation produced by positive charge

What is EM radiation produced by positive charge?

EM radiation produced by positive charge refers to the electromagnetic waves that are emitted when a positively charged particle undergoes acceleration. This can happen when the particle moves, changes direction, or experiences a change in its electric field.

How is EM radiation produced by positive charge different from negative charge?

EM radiation produced by positive charge is similar to that produced by negative charge, but the direction of the electric and magnetic fields are reversed. This results in a wave with a positive direction of propagation, compared to a negative direction in the case of negative charge.

What are some common sources of EM radiation produced by positive charge?

Some common sources of EM radiation produced by positive charge include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays. These waves are produced by a variety of processes, such as the movement of charged particles in a circuit, nuclear reactions, and thermal energy.

How does EM radiation produced by positive charge affect our daily lives?

EM radiation produced by positive charge plays a crucial role in our daily lives. Radio waves allow for communication through radios and cell phones, microwaves are used for cooking, infrared radiation is essential for thermal imaging and remote controls, visible light allows us to see, and X-rays and gamma rays are used in medical imaging and cancer treatment.

Can EM radiation produced by positive charge be harmful?

Yes, some forms of EM radiation produced by positive charge can be harmful to humans. For example, overexposure to ultraviolet radiation from the sun can cause sunburns and increase the risk of skin cancer. X-rays and gamma rays can also be harmful if not used properly. However, most forms of EM radiation produced by positive charge are not harmful and are essential for various applications in our daily lives.

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