The invention of a Newton, how was it measured back then?

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The discussion centers on the definition of a Newton as the force required to accelerate one kilogram at one meter per second squared. Participants express curiosity about the tools Newton used for measuring mass and acceleration, noting that he did not define the unit named after him. The conversation clarifies that the weight of an object on Earth is indeed the force exerted by the gravitational field on that mass, with a specific example given for a 10 kg mass resulting in a weight of 98 Newtons. It is emphasized that both the mass and the Earth exert equal forces on each other, in accordance with Newton's third law. The thread highlights the distinction between mass and weight, as well as the historical context of the Newton unit's definition.
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Hi, so I learned the definition of a Newton which is

Definition of Newton
- 1 Newton is the force needed to accelerate 1 kilogram of mass at the rate of 1 metre per second squared.
- 1N = kg*(m/s^2)

But I'm very curious about one thing
What tools did he use, and how could Newton actually measure the mass multiplied by the acceleration of an object precisely?
 
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Newton did not define the unit named after him. It wasn't named until over 200 years after his death.
 
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christian0710 said:
What tools did he use, and how could Newton actually measure the mass multiplied by the acceleration of an object precisely?
Newton was not involved in the definition. The definition was needed in order to separate mass (which is independent of location) and weight (which is dependent on location).
 
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Svein said:
Newton was not involved in the definition. The definition was needed in order to separate mass (which is independent of location) and weight (which is dependent on location).

Thank you very much - both of you. A questions comes to mind as you mention this

is it correctly understood that the weight of an object on Earth is the force that the gravitational field exerts on that mass? So if the mass is 10kg then it's weight is 10kg*9,8N = 98Newton? (do you say the gravitational field exerts 9,8N force on a mass, or that the gravitational field makes the mass exert a force of 98Newton?)
 
christian0710 said:
Thank you very much - both of you. A questions comes to mind as you mention this

is it correctly understood that the weight of an object on Earth is the force that the gravitational field exerts on that mass? So if the mass is 10kg then it's weight is 10kg*9,8N = 98Newton? (do you say the gravitational field exerts 9,8N force on a mass, or that the gravitational field makes the mass exert a force of 98Newton?)
Both the statements are true - the mass exerts a 98N force on Earth, and the Earth exerts a 98N force on the mass (Newton's 3rd law). It's just that Earth has so much mass that we don't see it move much at all (Newton's second law).
 
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I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...

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