Are momentum and centripetal acceleration related somehow?

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SUMMARY

The relationship between momentum and centripetal acceleration is defined by their dependence on velocity. Centripetal acceleration (a_c) is calculated as a_c = v²/R, where v is the velocity and R is the radius of curvature. Linear momentum (q) is expressed as q = mv, with m being mass. An increase in velocity affects both quantities: if velocity doubles, momentum doubles while centripetal acceleration quadruples. Thus, while they are related through velocity, they play different roles in their respective equations.

PREREQUISITES
  • Understanding of linear momentum (q = mv)
  • Knowledge of centripetal acceleration (a_c = v²/R)
  • Familiarity with the concept of radius of curvature
  • Basic grasp of kinematics and dynamics
NEXT STEPS
  • Study the derivation of centripetal acceleration from Newton's laws
  • Explore the implications of changing mass on momentum and acceleration
  • Learn about the role of force in circular motion and its relation to momentum
  • Investigate the effects of varying radius on centripetal acceleration
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Students of physics, educators teaching mechanics, and anyone interested in the dynamics of motion and forces in circular paths.

Sundown444
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I have been wondering, simple question, really: What is the relationship between momentum and centripetal acceleration, if there is one? Is there a relationship in terms of velocity, maybe, or is there none whatsoever?
 
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An acceleration is a rate of change of velocity, remembering that velocity involves both magnitude and direction. In the usual case, centripetal acceleration is related to the change in velocity associated with the change in direction. When you change the direction of motion, you change the momentum of the body as well. So, yes, they are related.
 
I see. Well, I have one more question. Centripetal Acceleration is proportional to the square of the velocity divided by the radius. How is the square of the velocity related to the velocity in momentum, if it is?
 
Dr.D's answer is neat, but if you're looking for something more I think you may want to clarify what you mean by being related; both of them have a dependency on velocity, yes, but that would make every cinematic quantity somehow related with each other, thus making your question a bit vague.
Sundown444 said:
I see. Well, I have one more question. Centripetal Acceleration is proportional to the square of the velocity divided by the radius. How is the square of the velocity related to the velocity in momentum, if it is?
Not sure if i get what you are asking here, but consider a point mass in motion along some curve: every single point P on the curve can be locally approximated by a circle of radius R_P (see osculating circle), so at every point you can compute a value for your centripetal acceleration a_c = \frac{v^2}{R_P}, so if you remember that linear momentum is q = mv you'll note that if velocity increase by a factor of 2, linear momentum will increase by the same factor, while centripetal acceleration will increase by a factor of 2^2=4.
Likewise, if you change the centripetal acceleration acting on the body by a factor k (without changing its istantaneous radius of curvature), its speed, and therefore its linear momentum, will change by a factor \sqrt{k}
 
Sundown444 said:
How is the square of the velocity related to the velocity in momentum
By a power of 2.
 
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mastrofoffi said:
Dr.D's answer is neat, but if you're looking for something more I think you may want to clarify what you mean by being related; both of them have a dependency on velocity, yes, but that would make every cinematic quantity somehow related with each other, thus making your question a bit vague.
Not sure if i get what you are asking here, but consider a point mass in motion along some curve: every single point P on the curve can be locally approximated by a circle of radius R_P (see osculating circle), so at every point you can compute a value for your centripetal acceleration a_c = \frac{v^2}{R_P}, so if you remember that linear momentum is q = mv you'll note that if velocity increase by a factor of 2, linear momentum will increase by the same factor, while centripetal acceleration will increase by a factor of 2^2=4.
Likewise, if you change the centripetal acceleration acting on the body by a factor k (without changing its istantaneous radius of curvature), its speed, and therefore its linear momentum, will change by a factor \sqrt{k}

I see. Well, beyond the square root of velocity in centripetal acceleration and such, there wasn't much else I was asking for, if anything at all. So, the velocity squared in centripetal acceleration is independent from the velocity in momentum, I take it?
 
Sundown444 said:
I see. Well, beyond the square root of velocity in centripetal acceleration and such, there wasn't much else I was asking for, if anything at all. So, the velocity squared in centripetal acceleration is independent from the velocity in momentum, I take it?
No, how can the velocity be independent from itself? I mean, it is the same velocity we are talking about, it just plays a different role in the 2 quantites, momentum being linear in v while centripetal acceleration is quadratic. In fact, as I showed you, with fixed mass and trajectory a change in centripetal acc implies a change in linear momentum and viceversa.
If what you are asking is "is the v^2 in the centripetal acceleration directly derivable from the linear momentum?" then for sure you can find some fancy way to derive it like that(consider a body under action of centripetal force, note that F = dq/dt, etc..) but it would be hardly meaningful with respect to the standard way of defining those quantities.
 
mastrofoffi said:
No, how can the velocity be independent from itself? I mean, it is the same velocity we are talking about, it just plays a different role in the 2 quantites, momentum being linear in v while centripetal acceleration is quadratic. In fact, as I showed you, with fixed mass and trajectory a change in centripetal acc implies a change in linear momentum and viceversa.
If what you are asking is "is the v^2 in the centripetal acceleration directly derivable from the linear momentum?" then for sure you can find some fancy way to derive it like that(consider a body under action of centripetal force, note that F = dq/dt, etc..) but it would be hardly meaningful with respect to the standard way of defining those quantities.

Yeah, that is what I meant to say, the playing a different role part. My bad. Sorry about that.
 

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