Is it Possible to Attain the Speed of Light by Combining Two Half-Speed Bodies?

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SUMMARY

The discussion centers on the concept of achieving the speed of light (c) by combining two bodies moving at half the speed of light (0.5c) in opposite directions. It is established that while 0.5c is attainable, the velocities do not add linearly due to the principles of special relativity. The formula w = (u + v) / (1 + uv/c²) demonstrates that combining two sub-light-speed velocities results in a maximum speed of 0.8c, which is still less than c. The second postulate of relativity asserts that all observers measure the speed of light as c, regardless of their own motion.

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  • Understanding of special relativity principles
  • Familiarity with the speed of light (c) and its implications
  • Knowledge of relativistic velocity addition formula
  • Basic comprehension of observer effects in physics
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  • Study the implications of the second postulate of special relativity
  • Learn about the relativistic velocity addition formula in detail
  • Explore the concept of simultaneity in special relativity
  • Investigate the effects of acceleration on measurements of light speed
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Physics students, educators, and anyone interested in the principles of special relativity and the nature of light speed measurements.

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Every one know that the speed of light "c" is unattainable but IS half the speed of life is attainable?
i.e 1/2(c)
If we get two bodies of 1/2(c) speed then by moving these bodies in opposite direction the spees of light is attainable?
Is it possible?
 
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A speed of 0.5c is attainable, but velocities don't add up like that in special relativity. Instead of w=u+v, the rule is

w=\frac{u+v}{1+\frac{uv}{c^2}}

With u=-0.5c and v=0.5c, you get w=c/(1+0.25)=0.8c.
 
I don't know about the details of relativity but know about it,s results.
Is from this equation the velocity of light is attainable or not by the motion of two bodies having speed less than C
 
It's not. If u<c and v<c, then w<c.
 
Since this is the Relativity section, think of the situation in terms of Special Relativity.
The 2nd postulate says that all observers measure the speed of light to be the same c.
So it doesn't matter to me how 'fast' any other object is traveling, I always measure c as c. I could accelerate for a long time, making me go a lot faster than other objects, doesn't change anything - we will each continue to measure c.
A consequence of this idea is that, as stated above, the (relative) speeds of individual moving objects does not add algebraically.
Ron
 
If we get two bodies of 1/2(c) speed then by moving these bodies in opposite direction the spees of light is attainable?
Is it possible?

yes. Fredriks answer is precisely correct as observed from either u or v,

but if these are the speeds of spaceships relative to earth, an observer will see the ships moving apart at speed c...but if each ship emitted light, the light from each would be observed at speed c among all observers...
 

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