Struggling to Understand Relativistic Phenomena

In summary: The length would increase because the speed of light would be traveling slower and slower, and the mass would increase because your body would be made of more matter. Time would slow down because the speed of light would be traveling slower and slower, and it would be like you were running in slow motion.
  • #1
meemosewa
9
0
This question has been driving me crazy all night.

The question reads:
If the speed of light were smaller than it is, would relativistic phenomena be more or less conspicious than they are now?

:confused: Honestly, i do not have a clue as to what the question is asking, and without understand thing the question, i have no way to answer it. I have read and reread the section in my book on the speed of light, and i do not understand it in the least bit... ANY HELP WOULD BE LOTS OF HELP!

THANK YOU!
 
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  • #2
Take some non-classical relativity equations, and look at what would happen if you made [tex]c[/tex] a smaller number. For example:
[tex]p = \frac{m_{0}v}{\sqrt{1-\frac{v^2}{c^2}}}[/tex].

What if [tex]c[/tex] were a smaller number - say, 0.5? Take it to the extreme! The change in momentum is an example of a relativistic phenomenon - would a large change in c have an impact on this phenomenon?

Take a look at some other equations of special relativity, and plug in ridiculously small values of [tex]c[/tex].
 
  • #3
This may not be within the scope of the question you were given but in order for the speed of light to be different both [itex]\mu_0[/itex] and [itex]\epsilon_0[/itex] would need to be changed thereby changing other things like the Bohr radius and electromagnetic quantities. Our scales of time and length would thereby change accordingly.
 
  • #4
unfortunately my class is material based, and not equation based. i should have mentioned this before, but do you have an explanation that is a little easier to understand? i appreciate the help, i just do not know what the equations and symbols represent... thanks!
 
  • #5
The speed of light in a vacuum is a constant value in any non-accelerating frame of reference, and it is a very high speed. To illustrate this, think of someone with a tube that bounces photons around vertically, who is on a train moving at 20 m/s. To the guy on the train the photons move only vertically, but to an observer on the ground they also move horizontally, making their total distance moved greater. Since speed is distance divided by time, and since light moves at the same speed for both of these peope, we can calculate the time it takes for a round trip from the top of the tube, to the bottom and back up for each observer. For the guy on the outside, the light traveled a greater distance at the same speed, so time happened faster for him than the guy on the train.

Using similar ideas, we can generalize by saying that as an object approaches the speed of light, its length decreases, its mass increases, and time slows down for it.

Now consider if the speed of light were walking speed, and tell us what you think would happen in your everyday world.
 

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  • #6
I understand your explanation, but let me try to answer your question...

If the speed of light were represented by a guy walking with a tube of protons that bounce vertically, then:

time would slow down. the length of each bounce would increase (because of relativity?) and the mass would be smaller?

i think i have it now, thank you for the visualization and easy to understand explanation!
 
  • #7
Unless your everyday world consists of guys who walk around with tubes of photons, I was getting at something slightly different :smile:

Since nothing can move faster than light, and you know the effects of moving near the speed of light, and if the speed of light were all of a sudden 10 km/h... what would happen to you if you went for a run. What is the fastest you could run then? How would your length, mass, and perception of time change?
 
  • #8
Mass increases as you reach the speed of light, and the speed of light is the maximum speed. If the speed of light became 10 m/s, then nothing could move faster than 10 km/s, and mass would increase much faster.

Increasing Mass Equation - notice that if the speed of light is smaller then your mass increases more.
[tex]m = \frac{m_{0}}{\sqrt{1-\frac{v^2}{c^2}}}[/tex]

The tube of protons (photons?) is a complicated way to think about it. Think about the increase in mass as you approach the speed of light, and how it would change if the speed of light were smaller.
 
  • #9
Saketh said:
The tube of protons (photons?)

I think I said photons?
 
  • #10
illwerral said:
Since nothing can move faster than light, and you know the effects of moving near the speed of light, and if the speed of light were all of a sudden 10 km/h... what would happen to you if you went for a run. What is the fastest you could run then? How would your length, mass, and perception of time change?

Then i would not be able to run very quickly at all. Everytihng would slow down to an extreme, including the speed of cars, and planes. My perception of time would chage in dramatic ways. Everything would take so long to complete. A trip to the grocery store would take days... I think this is an interesting way to view the concept. I understand the time portion... as for the rest, i guess my mass would increase and my length would be shorter? errr...

:rolleyes: i think i get the concept of the speed of light about as much as i can. Thank you for all of your help! I now understand that if the speed of light were slowed down it would have a HUGE impact on everything.

I DO APPERCIATE IT!
 
  • #11
Saketh said:
Mass increases as you reach the speed of light, and the speed of light is the maximum speed. If the speed of light became 10 m/s, then nothing could move faster than 10 km/s, and mass would increase much faster.
Not quite.
Mass would not increase much faster since it would be just as hard to go to say 50% of the speed of light is it was 10 m/s as it is when it is 299,792,458 meters/sec.

The speed of light is not always the same (in a vacuum). Inside a black hole light can go faster than 299,792,458 meters/sec.

By the way the speed of light in vacuum is exactly 299,792,458 meters/sec by definition!
 

FAQ: Struggling to Understand Relativistic Phenomena

What is the theory of relativity?

The theory of relativity, also known as the special and general theory of relativity, is a scientific theory developed by Albert Einstein in the early 20th century. It explains how the laws of physics apply to objects and events in different frames of reference, particularly at high speeds and in the presence of strong gravitational fields.

What is the difference between special and general relativity?

Special relativity deals with the principles of space and time for objects moving at constant speeds, while general relativity extends these principles to include non-uniform motion and the effects of gravity. Special relativity also includes the famous equation E=mc^2, while general relativity explains how gravity is caused by the curvature of spacetime.

How does relativity impact our understanding of the universe?

Relativity has revolutionized our understanding of the universe by providing a new framework for understanding the laws of physics. It has helped us to explain phenomena such as time dilation, length contraction, and the behavior of light in extreme conditions. It has also led to the discovery of new concepts, such as black holes and gravitational waves, which have greatly expanded our knowledge of the cosmos.

Why is it difficult to understand relativistic phenomena?

Relativistic phenomena can be difficult to understand because they often go against our common sense and everyday experiences. It can be challenging to wrap our minds around concepts like time dilation, where time can appear to move at different speeds for different observers, or the bending of light by gravity. Additionally, the mathematics and equations used to describe these phenomena can be complex and require a strong understanding of physics and mathematics.

How do scientists study and test the principles of relativity?

Scientists study and test the principles of relativity through a combination of theoretical and experimental methods. Theoretical physicists use mathematical models to make predictions about how objects and events behave in different frames of reference, while experimental physicists conduct experiments to gather data and test these predictions. Some of the most famous experiments that have confirmed the principles of relativity include the Michelson-Morley experiment and the observation of gravitational lensing.

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