Is F=ma the only way to define force?

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The discussion centers on the definition of force, specifically questioning whether F=ma is the only valid expression for measuring force. Participants argue that while F=ma serves as a foundational definition, alternative expressions like F=mdx/dt could theoretically be used. The conversation highlights that the concept of force can exist independently of Newton's second law, as demonstrated through examples like the behavior of springs. Ultimately, the consensus suggests that F=ma remains the most practical and widely accepted definition for deriving expressions for fundamental forces.

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I thought to myself yesterday: Is there really any way of measuring a force independent of F=ma? I don't see there is so you can more or less take F=ma as the definition of force and then use that to derive the expressions for the fundamental forces of nature. But then it occurred to me: Why did we then choose F=ma. Why didnøt we just pick F=mdx/dt and adjusted the expressions for the fundamental forces from that?
 
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aaaa202 said:
I thought to myself yesterday: Is there really any way of measuring a force independent of F=ma? I don't see there is so you can more or less take F=ma as the definition of force and then use that to derive the expressions for the fundamental forces of nature. But then it occurred to me: Why did we then choose F=ma. Why didnøt we just pick F=mdx/dt and adjusted the expressions for the fundamental forces from that?

http://en.wikipedia.org/wiki/Torsion_bar_experiment
 
aaaa202 said:
I thought to myself yesterday: Is there really any way of measuring a force independent of F=ma? I don't see there is so you can more or less take F=ma as the definition of force and then use that to derive the expressions for the fundamental forces of nature. But then it occurred to me: Why did we then choose F=ma. Why didnøt we just pick F=mdx/dt and adjusted the expressions for the fundamental forces from that?
This has been discussed at length in several threads eg: https://www.physicsforums.com/showthread.php?t=631147.

The concept of force exists independently of the second law eg. a standard spring exerts a standard force if stretched a standard distance. Double the number of such stretched springs and you double the force.

AM
 

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