A dimensional problem in relativistic mechanics

In summary, the equation being discussed is the relativistic Newton's second law, F=dp/dt. The issue being raised is that the first term on the right side, γ^3m/c^2, has the dimension of mass instead of force. However, it is noted that this term should actually be γ^3m/c^2 (v.a) v, indicating that a factor was missing in the original equation.
  • #1
ShayanJ
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[tex]{F}=\frac {{\gamma}^3 {m} {v}^2}{{c}^2} + \gamma {m} {a} [/tex]

You all know this equation.Relativistic Newton's second law.
The problem is as follows:
As you know [tex]\gamma[/tex] is dimensionless.So the first term of the right side has dimension of mass.but it should have the dimension of force!
what's wrong here?
thanks
 
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  • #2
Shyan said:
[tex]{F}=\frac {{\gamma}^3 {m} {v}^2}{{c}^2} + \gamma {m} {a} [/tex]

You all know this equation.Relativistic Newton's second law.
The problem is as follows:
As you know [tex]\gamma[/tex] is dimensionless.So the first term of the right side has dimension of mass.but it should have the dimension of force!
what's wrong here?
thanks

Hi Shyan. :smile:

F = dp/dt.

However, the equation that you write, I don't know it.
See http://en.wikipedia.org/wiki/Special_relativity (scroll down to the section on force).
It looks like you forgot a dv/dt term.

Harald
 
  • #3
You left out a factor. The first term is actually

γ3 m/c2 (v.a) v
 

1. What is a dimensional problem in relativistic mechanics?

A dimensional problem in relativistic mechanics refers to a situation where the units of measurement used to describe a physical quantity do not match up, leading to inconsistencies and difficulties in calculations. This can occur when combining concepts from both classical and relativistic mechanics, as the two theories use different units for certain physical quantities.

2. How can a dimensional problem be identified in relativistic mechanics?

A dimensional problem can be identified by checking the units of each term in an equation or by looking for inconsistencies in the units used throughout a calculation. For example, if the left side of an equation has units of time, but the right side has units of distance, this is a clear indication of a dimensional problem.

3. How can a dimensional problem be solved in relativistic mechanics?

To solve a dimensional problem in relativistic mechanics, it is important to use consistent units throughout the calculations. This may involve converting between different unit systems or using conversion factors to ensure that all units align. Additionally, it may be necessary to use equations specifically designed for relativistic mechanics to accurately describe the system.

4. What are the consequences of ignoring a dimensional problem in relativistic mechanics?

Ignoring a dimensional problem in relativistic mechanics can lead to incorrect calculations and incorrect interpretations of physical phenomena. This can result in faulty predictions and a lack of understanding of the underlying principles of the system being studied. In extreme cases, it can also lead to experimental errors and incorrect conclusions.

5. How does solving a dimensional problem in relativistic mechanics impact our understanding of the physical world?

Solving a dimensional problem in relativistic mechanics is crucial for accurately describing and understanding the physical world. By ensuring that all units are consistent and all calculations are accurate, we can gain a deeper understanding of the principles and laws that govern the behavior of objects in the universe. This can lead to advancements in technology and a better understanding of our place in the cosmos.

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