Answer:
The magnitude of the particle´s velocity is 4m/s (can´t change from the initial point to the final point) and the magnitude of the acceleration (centripetal acceleration) is 8 m/s². you have to considerate a particle moving with constant angular velocity (Uniform circular motion).
Explanation:
If the particle has constant angular velocity, you are in the presence of a uniform circular motion. That means the magnitude of the radial velocity is a constant and the relation between radial velocity and angular velocity is:
[tex]\omega=R*v[/tex] with R the circumference radius
In this kind of movement, the acceleration is perpendicular to the trajectory of the particle (centripetal acceleration). The expression of the magnitude of this acceleration is:
[tex]A_{c} =\frac{v^{2} }{R} =v*\omega=4*2\frac{m}{s^{2}} =8\frac{m}{s^{2}}[/tex]