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I just want your opinion in some questions: First of all, how do we define a physical quantity? Is it a mathematical creation that helps us describe something happening in nature? And all these formulas that we have come up with: example F=dp/dt . Are they mathematics or physics? When we say that F is force and it's a vector, what do we exactly mean? A vector is mathematical term and Force is a physics term: so we apply all the rules that are used in vectors to do calculations in order to come up with a vector that represents a physical quantity, like force? In other words, all the formulas are plain mathemaics , but the quantities used in them represent quantities in physics, that we have defined in a certain way? To sum up, we have come up with a way of describing physical quantities by numbers, and generally by mathematical creations, so we apply everything that is true for mathematics to these quantities to come up with mathematical formulas that connect the values of physical quantities through a function, example s=(1/2)*g(t^2) is a function in which t represents time and s distance, but in any other aspect is plain mathematics, and we can do anything that applies to mathematics, for example algebraic calculations, and come up with a right result, representing distance or any other quantity?And when we say that F=Gm*m'/(r^2) is the force between two objects with masses m and m' then we actually mean that if we put the value of their masses in this formula, taking the product of them and with consant G and then divide it with the number that represents the product of distance with distance then we come up with a number that represents the force between them?

Are all these right? I just want to make these things clear in my head

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# Physical quantities and definitions

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