If a particle moves in a circle describing equal angles in equal intervals of times, Its velocity vector:

Explanation

When a particle moves in a circle describing equal angles in equal intervals of time, it undergoes circular motion. In circular motion, the velocity vector changes continuously. Velocity is a vector quantity, meaning it has both magnitude and direction. In the case of circular motion, the magnitude of the velocity vector remains constant (if the speed is constant), but the direction changes continuously as the particle moves around the circle. This change in direction signifies that the velocity vector is not constant. Therefore, the correct answer is that the velocity vector changes in direction. The incorrect options are based on misunderstanding the nature of circular motion and the characteristics of velocity vectors.