Velocity as a function of distance problem

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The problem involves determining force, position, and force as a function of time for a ball with velocity defined as v(x) = ax-n. The acceleration is calculated as a = -nax-n-1, leading to the integration of acceleration with respect to time. The integration process reveals that (1/n+1)x^(n+1) = at, but the user struggles to express x in terms of a, n, and t. Further clarification on the integration steps and the relationship between variables is sought to complete the solution. The discussion emphasizes the importance of correctly handling the dependence of velocity on distance.
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Homework Statement



The velocity of a ball of mass 'm' varies with the distance v(x) = ax-n, where a and n are positive constants.

Determine F(x), x(t) and F(t).

Homework Equations


F = ma
a = dv/dt
v = dx/dt


The Attempt at a Solution


If velocity were the function of time, i would have done it with no problem. I determined the acceleration, which is -nax-n-1.
For v, i integrated 'a' with respect to t. But velocity's dependence in distance confused me. Any help will be highly appreciated.
 
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There is a simple way for these.
a=dv/dt. This can be written as a=dx/dt*dv/dx.
 
v = dx/dt = a*x^-n
So x^n*dx = a*dt.
Find the integration and then find x in terms of a, n and t.
Then d^2(x)/dt^2 will give acceleration in terms of a,n and t. from that you can find F(t)
Acceleration a = dv/dt = dv/dx*dx/dt = dv/dx*v. Then F(x) = ma
 
Last edited:
To rl.bhat

Thanks. I tried to follow your instruction.
Integration of x^n*dx = a*dt gave me (1/n+1)x^(n+1) = v. I didn't find x in terms of a, n and t.
 
(1/n+1)x^(n+1) = v.
This should be
(1/n+1)x^(n+1) = at
x^(n+1) =a(n+1)*t
x = ...?
 
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