Equations of motion problem

[phys2]

Homework Statement

So my main issue is with regards to when you integrate Newton's second law twice to get the position of a particle with respect to time. Why does everyone say that the first constant of your integration is initial velocity and second constant is initial position. Is there any logic behind that or is it just arbitary?
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Homework Equations

The Attempt at a Solution

 

[e^(i Pi)+1=0]

Because the second derivative of position is acceleration.

 

[BruceW]

It actually depends on what kind of function the acceleration is. But If the acceleration is a polynomial of time, then the constant of integration does equal the velocity at t=0.

You can realize this logically. If the acceleration is a polynomial, which you then integrate, then what must be the value of the polynomial at t=0?

P.S. welcome to physicsforums :)

Edit: I mean 'what is the value of the integrated polynomial, without the constant of integration, at t=0' Hmm, maybe I asked for too many steps at once. First, start off with a polynomial, then integrate it.

 

[azizlwl]

For a constant acceleration the position of the object is

$S=S{_0}+U{_0}t-\frac{1}{2}at^2$

$\frac {ds}{dt}=U{_0}-at$

$\frac {dv}{dt}=-a$

 

[asteriatic]

The reason for the first constant being the initial velocity and the second constant being the initial position is not arbitrary, but rather a result of the mathematics involved in solving the equations of motion. When integrating Newton's second law twice, the first constant arises as a result of the initial velocity term in the equation, while the second constant arises from the initial position term. These constants are necessary in order to fully determine the position of the particle with respect to time. Additionally, these constants have physical meaning in the context of the problem, as they represent the initial conditions of the particle's motion. Therefore, it is not arbitrary, but rather a result of the mathematical process and has a logical explanation.