Engineering [Intro Dynamics] How to obtain v(t) from v(r) in 3D?

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To obtain velocity as a function of time in three dimensions, the discussion explores whether it's feasible to derive v(t) from v(r) using integrals. The proposed approach involves integrating the position vector over the velocity function, questioning the validity of the time equation Δt = ∫(d r_x / v(r_x, r_y, r_z)). The conversation highlights the need for a formula that accommodates 2D or 3D trajectories, emphasizing the relationship between position, speed, and time. The discussion suggests that while the principles from 1D can be adapted, the complexity of multi-dimensional motion requires careful consideration of the velocity function's dependence on spatial coordinates. Ultimately, the feasibility of this approach remains a topic of inquiry.
Leo Liu
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Homework Statement
Conceptual question
Relevant Equations
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We know that in 1D, we can perform the following steps to obtain velocity in terms of time if the velocity is a function of position:
$$v=f(x)$$
$$dt=\frac{dx}{v}$$
$$t_2-t_1=\int_{x_1}^{x_2}\frac{dx}{v}$$
$$x(t)\rightarrow v(t)$$

But I wonder if it is possible to obtain ##\vec v(t)## from ##\vec v(\vec r)##? Does it even make sense to do something like $$\Delta t=\int_{r_{xi}}^{r_{xf}} \frac{d r_{x}}{v(r_x,r_y,r_z)}$$?
 
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The formula for time
t_{01}=\int_{l_0}^{l_1} \frac{dl}{v(l)}
where l is 2d or 3d trajectory of the particle whose position and speed are defined as function of l , would be of your interest.
 
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