How is speed defined in physics?

Speed is defined as the rate at which an object covers distance over time. This concept captures how fast something is moving, specifically quantifying this movement in terms of how much distance is traveled in a particular time frame. The formula for speed is commonly expressed as distance divided by time, indicating that if you know the distance an object travels and the time it takes, you can calculate its speed. This fundamental principle is essential in both physics and everyday situations where understanding movement is crucial, such as in sports, transportation, and various types of physical activities.

In understanding why the other choices do not define speed: acceleration refers to the change in velocity over time, which is a separate concept from simple speed; change in position over distance is somewhat misleading as it does not accurately convey how speed is calculated or represented; and force exerted over distance relates more to work and energy rather than speed. Thus, the correct option clearly captures the essence of speed in a meaningful and accurate way.