Velocity vector's change of direction

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When an object changes direction without altering its speed, the velocity vector changes only in direction, not in magnitude. The formula for velocity change, v = r/time, provides information on magnitude but lacks details about direction. Similarly, the acceleration vector's formula indicates magnitude but does not specify direction, which is only known to align with the velocity vector. The correct representations of these vector quantities are v = dr/dt and a = dv/dt. When velocity and acceleration are perpendicular, it indicates a change in direction without a change in speed.
boris16
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hi

If an object changes it's direction but not speed, then velocity vector will only change its direction but not magnitude.

* ... delta

*r... displacement vector

Formula for velocity change is *v = *r / *time

This formula doesn't tell us anything about the direction of *v, it tells us
only about its magnitude ?

Same could be said for acceleration vector a. Formula will only tell you acceleration vector's magnitude, but not it's direction ( well we do know the direction is same as *v, but since we don't know the direction of *v it's of little use ) ?

bye
 
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The correct "formulas" are

\vec v = \frac {d \vec r}{dt}

\vec a = \frac {d \vec v}{dt}

These are vector quantities. If the direction of the velocity changes without changing the speed, the velocity and acceleration are perpendicular to each other.
 
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