Why is the distance always greater than or equal to the displacement?

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Distance is always greater than or equal to displacement because distance measures the total path traveled, while displacement measures the shortest straight line between two points. In scenarios like traveling around a circle, the distance covered is greater than the displacement, which is represented by the diameter. Mathematically, this relationship is supported by the triangle inequality, indicating that the total distance (arc-length) cannot be less than the direct displacement (vector magnitude). Distance is a scalar quantity, while displacement is a vector, emphasizing their different properties. Consequently, distance can equal displacement only when traveling in a straight line, but it can never be less.
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Why is the distance never less than the displacement?
I can't seem to find a scientific explanation for it. :confused:
 
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think about traveling half way around a circle, the distance traveled would be half the circumference, and the displacement would be the diameter.

in this case distance > displacement

distance can be equal to the displacement (if you travel in a straight line), but it can never be less.
 
distance can be equal to the displacement (if you travel in a straight line), but it can never be less.

I know, but... why? Haha.
 
just think about the example i gave you and think of any other ones you can think of... the displacement will never be greater than the distance.

Think of distance as "distance travelled"

So if you're going from point A to point B in any situation you can think of (around curves, over mountains etc...) The distance traveled will be greater because you had travel "around" things.
The displacement is a straight line between point A and B, so it is always the shortest possible distance.
 
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Strictly speaking, distance is a magnitude but displacement is a vector.
So, yoiu really mean
"why is distance >= magnitude of displacement ?"

Mathematically,
\int \left| d\vec s \right| \geq \left| \int d\vec s \right|

Essentially, distance [ the arc-length of a curve from A to B ] is the sum of non-negative quantities.
The magntude of displacement [ the magnitude of a vector from A to B ] is the non-negative magnitude of a sum-of-(signed)-vector-quantities.
The proof of the inequality is essentially the triangle inequality.
 
distance is total distance traveled, displacement is from the initial location to the final location.
 
The displacement is the shortest way possible from the start to the finish (that is, it's a line); thus, nothing can be shorter.
 
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