Question

A particle has its position moved from r1=3i+4j to r2=i+2j.calculate the displacement vector (∆r)and draw the r1r2 and ∆r vector in a two dimensional Cartesian coordinate system

Answer 1

r₁ = 3i + 4j

r₂ = i + 2j

displacement is the shortest distance between two points.

In other words, displacement = final position - initial position.

∴ the displacement, ∆r = r₂ - r₁

∆r = i + 2j - 3i - 4j = -2i - 2j

Hence, displacement vector, ∆r = -2i - 2j