Why Are Initial Conditions x(0) and v(0) Preferred Over a(0) in ODE Solutions?

AI Thread Summary
Initial conditions in ordinary differential equations (ODEs) are typically chosen as position x(0) and velocity v(0) rather than acceleration a(0) because acceleration is inherently linked to the system's properties, such as spring constants in oscillatory systems. Specifying x(0) allows for a clear definition of the system's state, while v(0) provides necessary information about the initial motion. The acceleration a(0) is not independent, as it is derived from the initial position and the system's characteristics, making it less practical for initial condition selection. This relationship emphasizes the dependency of acceleration on both position and system parameters. Therefore, using x(0) and v(0) is more effective for solving ODEs.
littleHilbert
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Hi, World! Nice place here! My first post in this forum. :smile:

I've got a short question for a start.
If we wish to evaluate the constants for the general solution
x(t)=C_1e^{-{\lambda_1}t}+C_2e^{-{\lambda_2}t}
of this ODE:
\ddot{x}+2{\gamma}\dot{x}+{{{\omega}_0}^2}x=0
we can choose the initial conditions: x(0)=x_0,\dot{x}(0)=v_0
I cannot see at a glance why we can't choose an initial condition of acceleration and try to calculate the constants using this value. Why do we choose x_0,v_0 and not for example x_0,a_0 with a_0={{\lambda_1}^2}C_1+{{\lambda_2}^2}C_2?
 
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Hey, Guys...why silence?
Did I ask nonsense? :rolleyes:
I don't think it's nonsense.
In the meantime I came across some info on oscillations in Feynman's lectures.
It says we cannot specify acceleration with which the motion started because it is determined by the spring, once we specify x_0. But isn't the velocity also dependent on the properties of the spring then?
 
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