Find x(t) with Kx Force and Mass m | KxForce

AI Thread Summary
The discussion revolves around solving the motion of a particle of mass m under the influence of a force F(x) = kx, with initial conditions of starting position x0 and zero initial speed. Participants express confusion over the integration process and the correct application of acceleration in terms of velocity. There is a suggestion to apply integration rules while considering initial conditions to derive x as a function of time. Clarifications are made regarding the expression of acceleration and its relationship with velocity and time. The conversation emphasizes the importance of correctly setting up the equations to find the solution.
Ryan95
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Homework Statement


A particle of mass m is subject to force F(x)=kx with K>0. The initial starting position is x0 and the initial speed is zero. Find x(t).

Homework Equations


F(x)=kx
F=ma

The Attempt at a Solution


Honestly, I am totally lost on this. I've written acceleration as v(dv/dx) which gave me mv(dv/dx)=Kx and then tried separating variables to integrate, but once I do that, I'm totally lost as I end up with m(v2/2)=K(x2/2).
 
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Ryan95 said:
Honestly, I am totally lost on this. I've written acceleration as v(dv/dt) which gave me mv(dv/dx)=Kx and then tried separating variables to integrate, but once I do that, I'm totally lost as I end up with m(v2/2)=K(x2/2).

i wonder how one can write acceleration as v..dv/dt as we know it as rate of change of velocity with time.. may be a typo.
now dv/dt can be expressed as d/dxof v multiplied by dx/dt .

i think you should proceed with the analysis as per the rule of integration and have initial conditions at t=0 and try to find x as a function of t. as one normally does with constant forces.
 
drvrm said:
i wonder how one can write acceleration as v..dv/dt as we know it as rate of change of velocity with time.. may be a typo.
now dv/dt can be expressed as d/dxof v multiplied by dx/dt .

i think you should proceed with the analysis as per the rule of integration and have initial conditions at t=0 and try to find x as a function of t. as one normally does with constant forces.

Oh, thank you, yes that was a typo. I've edited the post.
 
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