Understanding the Concepts

* Acceleration: The rate at which an object's velocity changes. It's measured in meters per second squared (m/s²).

* Initial Velocity (v₀): The starting velocity of the car (30 m/s).

* Final Velocity (v): The velocity of the car after it stops (0 m/s).

* Time (t): The time it takes the car to stop (3.0 seconds).

Formula

The formula for acceleration is:

acceleration (a) = (final velocity (v) - initial velocity (v₀)) / time (t)

Calculation

1. Plug in the values:

a = (0 m/s - 30 m/s) / 3.0 s

2. Solve:

a = -30 m/s / 3.0 s

a = -10 m/s²

Answer

The acceleration of the car is -10 m/s². The negative sign indicates that the car is decelerating (slowing down).