How Is Velocity Expressed as a Function of Position with Given Power Input?

AI Thread Summary
The discussion focuses on deriving velocity as a function of position for a vehicle moving along a track with power input expressed as alpha*x^1/2, where alpha is a constant and x is the distance from the start. The initial velocity is zero, and there is no energy dissipation. The user attempts to manipulate the power equation, relating it to kinetic energy, but struggles to find a useful solution. Another participant suggests using a differential equation approach by substituting dv/dt with dv/dx multiplied by velocity. The conversation emphasizes the need for guidance in solving the resulting differential equation for velocity as a function of position.
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Power to a vehicle moving along a track is alpha*x^1/2. No dissipation. alpha is constant x is distance from beginning of the track. zero initial velocity.
What is Velocity as function of position?

P=d KE/dt
P=d(1/2 m v^2)/dt
P=1/2 m d((dx/dt)^2)/dt
P=1/2 m 2 v dv/dt
alpha x^1/2 = 1/2 m 2 v dv/dt

And that is as far as I get. After some random manipulations I was not able to yield anything useful. Some assistance or guidance would be greatly appreciated. Thank you.

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dv/dt=dv/dx*dx/dt = dv/dx *v.

use this in your last formula then solve the differential equation for v(x).

ehild
 
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