Particle Velocity and Distance in a Straight Line with -2v Acceleration

AI Thread Summary
The discussion focuses on a particle with acceleration defined as a = (-2v) m/s², where the initial conditions are v = 20 m/s at s = 0 and t = 0. A user attempts to find the particle's velocity as a function of position and the distance it travels before stopping. They initially use integration to relate time and velocity but encounter difficulties. Another participant suggests using the relationship a = (dv/dt) = v(dv/ds) to express velocity in terms of displacement. This approach is recognized as helpful for solving the problem.
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Homework Statement


A particle is moving along a straight line such that its acceleration is defined as a = (-2v) m/s^2, where v is in meters per second. If v = 20 m/s when s = 0 and t = 0, determine the particle's velocity as a function of position, and the distance the particle moves before it stops.


Homework Equations


Basic kinematics equations


The Attempt at a Solution


I tried using dt = dv/a and integrating that, and I got t = (ln20 - lnv)/2, then I tried substituting it into s = s0 + v0t + (1/2)at^2, and now I'm stuck. Any help would be appreciated. Thanks :)
 
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Use the fact that

a= \frac{dv}{dt}=v \frac{dv}{ds}

this will help you get velocity in terms of displacement.
 
Oh right. Thanks a bunch :)
 
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