A particle moves with constant speed in a circle of radius 4 cm. It takes 8 s to make a complete trip. Draw the path of the particle to scale, and indicate the particle’s position at 1-s intervals. Draw displacement vectors for each interval. These vectors also indicate the directions for the average-velocity vectors for each interval. Find graphically the change in the average velocity Δv for two consecutive 1-s intervals. Compare Δv/Δt, measured in this way, with the instantaneous acceleration computed from a = v2/r.