I just found a new way to calculate Force

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    Force
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Discussion Overview

The discussion revolves around a proposed new formula for calculating force based on mass, velocity, and time, without explicitly calculating acceleration. Participants explore the implications and validity of this formula in the context of classical mechanics.

Discussion Character

  • Debate/contested
  • Mathematical reasoning
  • Technical explanation

Main Points Raised

  • One participant introduces a formula for force: F = (m/t)v, claiming it is more efficient than calculating acceleration.
  • Another participant points out that the proposed formula simplifies to F = ma, indicating that it ultimately relies on the concept of acceleration.
  • Concerns are raised about the implications of the formula, suggesting that it leads to the conclusion that force decreases as time increases, which is questioned by other participants.
  • Some participants argue that the formula does not align with experimental observations, particularly in scenarios like free fall where force increases with time.
  • A later reply discusses the importance of consistency with experimental data when formulating physics equations, indicating that the proposed formula may not hold true in practical applications.
  • Another participant elaborates on the relationship between force, mass, and velocity, suggesting that the formula may only apply under specific conditions, such as constant acceleration.
  • There is a discussion about the rate of change of momentum and how it relates to force, with references to more complex scenarios involving variable mass.

Areas of Agreement / Disagreement

Participants express differing views on the validity and implications of the proposed formula. There is no consensus on whether the formula accurately represents the relationship between force, mass, and velocity, and multiple competing interpretations are presented.

Contextual Notes

Some participants note that the proposed formula may not account for varying conditions such as changing mass or acceleration, and that it appears to contradict established principles in physics.

John Clement Husain
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I found a new way to calculate force without getting the acceleration when you have velocity, mass, & time.
F = (m/t)v
I just find this more efficient than getting the acceleration, why not use one formula.
 
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But as acceleration is change of velocity per time, you get ##F=(m/t)v=(mv/t)=m(v/t)=ma##, which is acceleration again.
 
So according to your formula, force always decreases as time increases. Is this what you observe?
 
Dale said:
So according to your formula, force always decreases as time increases. Is this what you observe?
It seems so, yes
 
fresh_42 said:
But as acceleration is change of velocity per time, you get ##F=(m/t)v=(mv/t)=m(v/t)=ma##, which is acceleration again.
yeah, I just stated that I don't have to go to a=v/t anymore
 
John Clement Husain said:
It seems so, yes
No, it doesn't. In fact, as an object falls from a great distance the force increases as time increases, in direct opposition to your formula.

When you write a formula in physics, it is important to check if it is consistent with experiment. Yours is not.
 
Dale said:
No, it doesn't. In fact, as an object falls from a great distance the force increases as time increases, in direct opposition to your formula.

When you write a formula in physics, it is important to check if it is consistent with experiment. Yours is not.
oh, I see...
also in my formula, force increases due to it's velocity. The faster the object, the greater the force?
but the formula does not contend with reality though, I shall take a note on that, thanks
 
John Clement Husain said:
oh, I see...
also in my formula, force increases due to it's velocity. The faster the object, the greater the force?
but the formula does not contend with reality though, I shall take a note on that, thanks
Also your understanding of force only works for constant accelerations.

constant a and constant m:
The force equation is F=ma, we could know the change in velocity Δv and the amount of time it took for that change to occur Δt. Then acceleration is a constant a=Δv/Δt. You could them formulate an equation F=(m/Δt)*Δv but this is trivial.

variable a and m:
Force eq. is F=dp/dt. this is the rate of change of momentum using differential calculus. You could have a changing m in a rocket, where the acceleration and velocity change as the rocket flies up, but the mass decreases as huge containers of fuel are emptied. Since p=mv, the force equation could read F=d(mv)/dt and your discovery is actually quite meaningful as you have noticed that Forces aren't limited to changes in velocity over time only.
 
John Clement Husain said:
also in my formula, force increases due to it's velocity. The faster the object, the greater the force?
Yes, good observation. It would mean that objects at rest would get stuck because v=0 so F=0. You could throw a ball up and have it never come down but just rest at the apex forever, and you would never be able to get out of bed in the morning.
 
  • #10
John Clement Husain said:
I found a new way to calculate force without getting the acceleration when you have velocity, mass, & time.
F = (m/t)v
I just find this more efficient than getting the acceleration, why not use one formula.

You could have written:

##F = m\frac{dv}{dt}##
 

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