When braking on a straight section of the road, the vehicle speed decreases from 20 m / s to 10 m / s within 5 s.

When braking on a straight section of the road, the vehicle speed decreases from 20 m / s to 10 m / s within 5 s. What is the acceleration of the car, provided that it remains constant while driving.

If the acceleration of the body throughout the entire deceleration remained constant, then this movement is equally slow.
a = delta V / t = 10/5 = 2m * s ^ 2
Since the body slows down, we take the negative projection of the acceleration, i.e. a = -2 m / s ^ 2