How Can an Object Emit Light/Radiation Without Energy Source?

In summary, the conversation is discussing the theory that objects moving at high speeds emit light at the same speed as stationary objects. This is due to their internal energy and relative velocity, not necessarily a specific energy source. The example of a computer screen emitting light while being stationary but still having an energy source is used to explain this concept. The focus is on relative velocity and not the presence or absence of an energy source.
  • #1
richport
2
0
Can anyone tell me how an object can emit light/radiation when it has no energy source?
 
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  • #2
It must have some source of energy to emit light/radiation. Can you give an example of something that emits light/radiation without any source of energy?.
 
  • #3
I can't really give an example, but I was reading an article that explained the theory that an object moving at great speed emits radiation/light at the same speed as a stationery object. My thought was that if the stationary object has no energy source, how can emit anything?
 
  • #4
It's still unclear to me
 
  • #5
richport said:
I can't really give an example, but I was reading an article that explained the theory that an object moving at great speed emits radiation/light at the same speed as a stationery object. My thought was that if the stationary object has no energy source, how can emit anything?
All objects have an internal energy based on their temperature. As they emit light, they cool down.
 
  • #6
richport said:
I can't really give an example, but I was reading an article that explained the theory that an object moving at great speed emits radiation/light at the same speed as a stationery object. My thought was that if the stationary object has no energy source, how can emit anything?

Is there anything in that article that implies no energy source? The point of the article, or at least what you say of it, is that if an object moving at high speed relative to you emits a light radiation (from whatever energy source) then you will see that light coming to you at the same speed as light coming from a stationary object (from whatever energy source). Where did you get the idea that the stationary object "has no energy source". This computer screen that I am looking at that is spitting large numbers of photons at me (and God know what other energy) is stationary relative to me and certainly does have an energy source- I just plugged it in!

The point of what you are reading is not "energy source", it is relative velocity. If you are standing on the side of a road and another person standing on the road (so stationary relative to you) throws a ball to you with speed (relative to him) 30 m/s, then it comes to you at (relative to you) 30 m/s. At the same time a truck comes toward you at 70 km/hr= 20 m/s and a person in the truck throws a ball at you at (relative to him) 30 m/s, then it comes at you at (relative to you) 20+ 30= 50 m/s.

That's the "Newtonian physics" calculation. "Einsteinian physics" would give a slightly different answer but, because the velocities involved are much less than the speed of light, you couldn't measure the distance.

Now, suppose that instead of throwing a ball, both people shine a light at you at (relative to each of them) c, the speed of light. Newtonian physics say that the light from the truck would be coming at you (relative to you) at c+ 20 m/s. Einsteinian physics say the light from both would be coming at you at c. It doesn't matter how fast the source of the light is moving, the light comes toward you at speed c.

That has nothing to do with a "source of energy". I think you are misunderstanding if you think it is talking about light without a source of energy.
 

1. What is the concept of an object emitting light without an energy source?

The concept of an object emitting light without an energy source is known as luminescence. It occurs when an object absorbs energy from its surroundings and converts it into light energy, without the need for a continuous external energy source.

2. How does an object emit light without an energy source?

An object can emit light without an energy source through a process called spontaneous emission. This occurs when an object has excess energy stored in its atoms, which causes them to release photons of light. This energy can come from sources such as heat, friction, or chemical reactions.

3. What are the different types of luminescence?

There are three main types of luminescence: fluorescence, phosphorescence, and bioluminescence. Fluorescence occurs when an object absorbs and immediately re-emits light, while phosphorescence involves a delay in the emission of light. Bioluminescence, on the other hand, is the production of light by living organisms.

4. Can all objects emit light without an energy source?

No, not all objects can emit light without an energy source. Only certain materials, such as phosphors and certain living organisms, have the ability to emit light through luminescence. Other objects may reflect or scatter light, but they cannot emit it without a continuous external energy source.

5. What are some real-life examples of objects emitting light without an energy source?

Some real-life examples of objects emitting light without an energy source include glow-in-the-dark toys, fireflies, and glow sticks. These objects all rely on luminescence to produce light without the need for a continuous external energy source.

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