Velocity vector equals displacement vector divided by time interval (3-7)

Question 1 of 4

Question

$\textbf{Velocity vector}$ for the object over a very short time interval from time $t_1$ to a later time $t_2$

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Question

$\textbf{Displacement vector}$ (change in position) of the object over the short time interval

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Question

$\textbf{Elapsed time}$ (change in position) for the time interval

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Review

By analogy to what we did for one-dimensional motion in Chapter 2, we define the object's instantaneous velocity vector $\vec{v}$ (or just velocity vector for short) at a given point along the trajectory as follows: Take the displacement $\Delta\vec{r} = \vec{r_2} - \vec{r_1}$ for a very short time interval around that point and divide it by the duration $\Delta{t} = t_2 - t_1$ of the interval.