Movitation For Definitions In Physics

[Bashyboy]

Hello,

I noticed in my physics textbook that we define certain relationships to be true. I can see how this is considerably helpful in deriving other relationships from these definitions; for instance, take position: we define these quantities to be so, and from it we can define other quantities like velocity, acceleration, etc. Moreover, most of the time these definitions are well-grounded and intuitive. However, at other times they aren't. To serve as some examples: force, torque, and electric fields. How were these things defined? What was the reasoning used to define these quantities? What are the motivations for these definitions?

 

[ModusPwnd]

The motivation for all definitions in physics is to be able to create descriptive and predictive models of our observations. If we define force, torque, and electric fields the way we do, we get powerful models. If we define them other ways, we dont.

 

[Bashyboy]

So, the way in which we define something is somewhat of a result of "trial-and-error?" That is, keep trying definitions until we find a definition that best describes something or fits experimental data?

 

[ModusPwnd]

So, the way in which we define something is somewhat of a result of "trial-and-error?" That is, we find a definition that best describes something or fits experimental data?

Yes, experiment is generally the final arbiter of whether a definition is useful. How you get the definition doesn't matter, trial and error, intuition, logic, wild guess, burning bush, whatever. Of course its interesting to read about how definitions came about, it gives insight into the process of science. But as far as theories of science are concerned, it doesn't matter at all how you come up with a definition. All that matters is if the definition increase our ability to predict and describe observations or not.

 

[pmacias]

I can understand your curiosity about the definitions used in physics. It is important to note that these definitions are not arbitrary or randomly chosen, but rather they are carefully crafted based on observations, experiments, and theoretical models. The definitions in physics serve as the building blocks for understanding the natural world and making predictions about it.

Forces, torque, and electric fields are all fundamental concepts in physics, and their definitions were developed through a combination of empirical evidence and mathematical reasoning. For example, the concept of force was first defined by Sir Isaac Newton as the product of mass and acceleration, based on his observations of objects in motion. This definition has been refined and expanded upon over time, as our understanding of the natural world has grown.

Similarly, torque was defined as the product of force and the distance from the pivot point, based on observations of rotational motion. And electric fields were defined by Michael Faraday and James Clerk Maxwell based on their experiments with electricity and magnetism. These definitions have been further refined and expanded upon with the development of theories such as electromagnetism and quantum mechanics.

The motivation for these definitions is to accurately describe and quantify the physical phenomena that we observe in the world around us. By defining these quantities, we are able to make predictions and calculations that can be tested and verified through experiments. This allows us to better understand the underlying principles of nature and how they govern the behavior of matter and energy.

In conclusion, the definitions used in physics are crucial for understanding and explaining the natural world. They are based on careful observations, experiments, and theoretical models, and serve as the foundation for further scientific advancements. As our understanding of the universe continues to evolve, these definitions may also evolve and be refined, but they will always play a vital role in our quest to unravel the mysteries of the universe.