Which situation describes a negative acceleration? (1 point)
A. a diver jumping off a diving board and falling to the swimming pool below
B. a bicycle increasing its velocity as the rider pedals harder
C. a runner slowing down at the end of a race
D. a swimmer moving at a constant velocity
The Correct Answer and Explanation is:
The correct answer is C. a runner slowing down at the end of a race.
Explanation of Negative Acceleration
Negative acceleration, also known as deceleration, occurs when an object decreases its velocity over time. This concept can be understood through the lens of acceleration, which is defined as the rate of change of velocity with respect to time. If the velocity of an object is decreasing, the acceleration will have a negative value, indicating that the object is slowing down.
In the context of the given options, let’s analyze each situation:
- A diver jumping off a diving board and falling to the swimming pool below: In this scenario, the diver is accelerating downward due to the force of gravity. The acceleration is positive in the downward direction, increasing the diver’s velocity as they fall.
- A bicycle increasing its velocity as the rider pedals harder: This situation describes positive acceleration. The bicycle is gaining speed as the rider exerts more force, indicating an increase in velocity over time.
- A runner slowing down at the end of a race: This situation illustrates negative acceleration. As the runner approaches the finish line, they intentionally reduce their speed, resulting in a decrease in velocity. Here, the acceleration is negative because the runner’s velocity is declining.
- A swimmer moving at a constant velocity: In this case, the swimmer is not experiencing any acceleration, whether positive or negative. Constant velocity means that the speed and direction remain unchanged, so there is no acceleration present.
Thus, option C is the only one that accurately depicts negative acceleration. Understanding this concept is crucial in various fields, including physics, sports science, and everyday scenarios, as it helps to analyze motion and the forces acting on objects. Negative acceleration plays a significant role in activities requiring controlled deceleration, such as running, driving, and cycling.