(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

For t < 0, an object of mass m experiences no force and moves in the positive x direction with a constant speed v_{i}. Beginning at t = 0, when the object passes position x = 0, it experiences a net resistive force proportional to the square of its speed: F_{net}= −mkv^{2}, where k is a constant. The speed of the object after t = 0 is given by

v = v_{i}/(1 + kv_{i}t).

(a) Find the position x of the object as a function of time. (Use the following as necessary: k, m, t, and vi.)

(b) Find the object's velocity as a function of position. (Use the following as necessary: k, m, t, vi, and x.)

2. Relevant equations

a = Δv/Δt

v = Δx/Δt

3. The attempt at a solution

I am suspecting that I need to integrate the given function to find the position function? I know that v = Δx/Δt, so we should have:

dx/dt = v_{i}/(1 + kv_{i}t)

then we need to take the definite integral from x_{0}to x_{f}or just 0 to x_{f}. My calculus is a bit rough, but isn't this some sort of a separable differential equation? So we need to make all the x's and t's all on one side? Right now that seems, well, impossible since we have no x's? So do I need to find something involving v and x, then relate/substitute so I only have x's and t's? Help please...

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# Homework Help: Integrating velocity equation to find position?

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