Question

When a moving car is brought to a stop with the brakes, its acceleration vector is 29. (a) in the same direction as its velocity vector b) in the opposite direction as its velocity vector c) equal to zero (d) directed downward

Answer 1

To develop this problem we will apply the concepts related to the kinematic equations of motion, specifically that of acceleration. Acceleration can be defined as the change of speed in an instant of time, mathematically this is

`\vec{a} = \frac{\vec{v_2}-\vec{v_1}}{\Delta t}`

If a mobile is decreasing its speed (it is slowing down), then its acceleration is in the opposite direction to the movement. This would imply that the acceleration vector is opposite to the velocity vector.

Therefore the correct answer is B.