Practice question · Multiple choice
A hiker walks 3 km east, then 4 km north. Their GPS "displacement" reads 5 km, but their pedometer reads 7 km. Which statement explains the disagreement?
Hints
- Draw the two legs as arrows tip-to-tail. What is the straight arrow from start to finish?
- , the most famous triangle in mathematics.
Show the answer
C. Displacement is a vector sum, not a total
Why
Vectors add geometrically, not arithmetically: perpendicular legs of 3 and 4 compose into a displacement of 5. Distance walked (a scalar) and displacement achieved (a vector) answer different questions, the core distinction of vector thinking.
Practise Vectors in 2D and 3D
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