Is Hooke's law related to the time-squared rate of acceleration?

AI Thread Summary
The discussion clarifies that there is no direct connection between Hooke's law and the time-squared rate of acceleration related to gravity. It emphasizes that acceleration is defined as distance over time squared, and in the context of gravity, it is influenced by the inverse square law. The acceleration of falling bodies is determined by the local gravitational field strength, which depends on the masses involved and their distance from each other. Additionally, Hooke's law describes a different relationship where force is proportional to displacement, not following an inverse square law. Ultimately, the two concepts operate independently within their respective frameworks.
jbmolineux
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Is there a connection between the inverse square law of gravity and the time-squared rate that bodies fall (i.e. (32ft/second)/second))?
 
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jbmolineux said:
Is there a connection between the inverse square law of gravity and the time-squared rate that bodies fall (i.e. (32ft/second)/second))?

Not reallly. It doesn't matter how a force is related to distance between the objects, acceleration (by definition) is (distance/second)/second.
 
For gravity, inverse square law meas that acceleration is a function of distance, so typically chain rule is used to convert time based acceleration into position based acceleration. Define the two masses as m1 and m2 :

a = dv/dt = v dv/dr = -G (m1 + m2) / r2

For an initial distance r0 and final distance r1, the above equation is integrated twice. The first integration isn't too bad, but the second one is complicated, and you end up with time as a function of initial and final distance, which can't be converted into distance as a function of time.
 
jbmolineux said:
Is there a connection between the inverse square law of gravity and the time-squared rate that bodies fall (i.e. (32ft/second)/second))?
The rate at which falling bodies accelerate is the local strength of the gravitational field.
 
A.T. said:
The rate at which falling bodies accelerate is the local strength of the gravitational field.
For a two body system, this would be the rate of acceleration towards a common center of mass for the two body system (use the common center of mass as the source for a reference frame). Each mass accelerates towards the common center of mass based on the gravitational field of the "other" mass.
 
jbmolineux said:
Is there a connection between the inverse square law of gravity and the time-squared rate that bodies fall (i.e. (32ft/second)/second))?

I can falsify your notion of the universality of such a connection. Consider Hooke's law, where the force is proportional to the displacement from equilibrium, i.e. not an inverse square law. Yet, the acceleration of the oscillating mass is still L/T2.

One has nothing to do with the other. One is the relationship between force and distance from the source of that force. The other is the dimension of a quantity.

Zz.
 
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