Chapter 1 - Concepts of Motion - Exercises and Problems - Page 28: 5

Since the ball is falling freely under gravity, (i.e, a constant acceleration), its velocity increases in the direction of the acceleration. Hence, the length of the velocity vector too increases.

Since the ball is falling freely under gravity, (i.e, a constant acceleration), its velocity increases in the direction of the acceleration. Hence, the length of the velocity vector too increases.