Understanding the Concepts
* Acceleration: The rate of change of velocity over time.
* Initial Velocity (v₀): The train's speed before braking (54.8 m/s).
* Final Velocity (v): The train's speed after braking (we assume it comes to a stop, so this is 0 m/s).
* Time (t): The time it takes to decelerate (39 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 - 54.8 m/s) / 39 s
2. Calculate:
a = -54.8 m/s / 39 s
3. Result:
a ≈ -1.405 m/s²
Interpretation
* The acceleration is negative because the train is slowing down (decelerating).
* The acceleration is approximately -1.405 m/s². This means the train's velocity decreases by 1.405 meters per second every second.
