Is Object 2 Traveling at Double the Speed of Light Relative to Object 1?

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In summary, we discussed the concept of the speed of light and its relation to the speed of material objects. It is true that no material object can exceed the speed of light. If two objects are moving in opposite directions at close to the speed of light, their relative speed to each other would still be below the speed of light. We also mentioned that particles with zero rest mass, such as photons, can travel at the speed of light. This is because they have no mass. Overall, the speed of light and mass are closely linked and there is no causality between them.
  • #1
expscv
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i was curious ,


is it ture that nothing can exceeds the speed of light, such all object (except photon) max speed is "speed of light" ?


2. if both object travel close to light of speed, but in oppsite direction

so realvtive to object 1, is object 2 travel at double of "speed of light"??
 
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  • #2
Yes, it is true that no material object (with non-zero rest mass) can travel at (or faster than) the speed of light.

If two objects are moving with, say, 0.99c (99% of the speed of light) relative to some third object (every speed has to be relative to something) going in opposite directions then the speed of each one, relative to the other, is (0.99c+ 0.99c)/(1+ (.99c)(.99c)/c2)= 1.98c/(1.9801)= 0.9999c.
 
  • #3
The formula HallsofIvy used is from Einstein's Special Relativity, which is the theory we must use to deal with such speeds.
 
  • #4
Here is the full formula in case you wanted to know:

[tex] u' = \frac {v+u}{1 + \frac{vu}{c^2}} [/tex]
 
  • #5
All particles with a rest mass greater than 0 travel at below the speed of light.
Particles with 0 rest mass only travel at light speed.
Particles with less than 0 rest mass should, if they exist, travel at only greater than light speed.
 
  • #6
whydoyouwanttoknow said:
All particles with a rest mass greater than 0 travel at below the speed of light.
Particles with 0 rest mass only travel at light speed.
Particles with less than 0 rest mass should, if they exist, travel at only greater than light speed.


oh? so photon is equal to 0 rest mass?

becasue it can travel exactly at speed of light?
 
  • #7
expscv said:
oh? so photon is equal to 0 rest mass?

becasue it can travel exactly at speed of light?

Yeah, photons have no mass.
 
  • #8
expscv said:
oh? so photon is equal to 0 rest mass?

becasue it can travel exactly at speed of light?

not exactly, *ahem*

A photon can travel at the speed of light because it has zero rest mass
 
  • #9
Are you sure there is "causality" here? c speed and 0 mass are pretty much hand in hand IMO. I would say either way to say it is good.
 

1. Is it true that max speed is a fixed value?

No, max speed can vary depending on different factors such as the object's mass, the force applied, and the medium it is moving through.

2. What is the maximum speed possible?

According to the theory of relativity, the maximum speed possible is the speed of light, which is approximately 299,792,458 meters per second in a vacuum.

3. Can an object exceed the maximum speed?

No, according to the theory of relativity, no object can travel faster than the speed of light. This is a fundamental principle of physics.

4. Does the maximum speed change in different environments?

Yes, the maximum speed can change in different environments. For example, light travels slower in water than in a vacuum, but it still remains the fastest speed possible in that medium.

5. How is the maximum speed calculated?

The maximum speed is calculated using the equation c = λf, where c is the speed of light, λ is the wavelength, and f is the frequency. This is known as the speed of light constant.

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