Distance vs. Displacement: What's the Difference?
Read the comparison below, or explore it visually. Create a visual lesson comparing distance and displacement using available credits or plan allowance.
Distance is the total length of the path an object travels, while displacement is the straight-line change in position from start to finish, including its direction. Distance is a scalar that can only grow as you move, but displacement is a vector that can shrink or become zero; an athlete running one full lap of a 400 m track covers 400 m of distance with zero displacement.
At a glance
| Distance | Displacement | |
|---|---|---|
| Definition | Total length of the path travelled | Shortest straight line from start to end |
| Type of quantity | Scalar: magnitude only | Vector: magnitude and direction |
| Can it be zero? | Only if the object has not moved | Yes, whenever it returns to its start |
| Depends on path? | Yes, the route taken matters | No, only start and end points matter |
| Comparison | Always greater than or equal to displacement | Magnitude never exceeds the distance |
Which should you use?
Distance is the useful measure when the route matters, such as the kilometres an auto-rickshaw meter charges for or the fuel a car burns on a winding ghat road.
Displacement is the useful measure when only the net change in position matters, such as how far and in which direction a ship ends up from port, or a drone's position relative to its launch point.