1.
A particle is moving westward with velocity v⃗1=5 m/s\vec{v}_1 = 5\,\mathrm{m/s}. Its velocity changes to v⃗2=5 m/s\vec{v}_2 = 5\,\mathrm{m/s} northward. The change in velocity vector (Δv⃗=v⃗2−v⃗1\Delta\vec{v} = \vec{v}_2 - \vec{v}_1) is