Final answer:
The runner's average speed can be calculated by dividing the distance by the time taken. For example, Usain Bolt's average speed during his world record 100-meter dash was 10.4 m/s. The concept of relative velocity can be illustrated by comparing the speeds of two marathon runners, where the difference in their speeds indicates their relative velocity.
Step-by-step explanation:
The runner's average speed in meters per second (m/s) can be calculated using the provided information. In the case of Usain Bolt, who set a world record in the 100-meter dash in 2009, his average running rate was 10.4 m/s. This speed is derived by dividing the total distance covered, which is 100 meters, by the time taken to cover that distance, which was 9.58 seconds, giving us 100 m / 9.58 s = 10.4 m/s. This calculation demonstrates how to determine the average speed when the distance and time are known. For an Olympic-quality sprinter with an average speed of 10 m/s, one can predict the time it would take to cover a different distance, such as 25 meters, by rearranging the equation to solve for time, resulting in 25 m / 10 m/s = 2.5 seconds.
In the context of calculating relative velocity, as shown in question 54, we would subtract the speed of the front runner from the second runner to find their relative speed. For example, if the front runner has a speed of 3.50 m/s and the second runner has a speed of 4.20 m/s, the relative speed of the second runner to the front runner would be 4.20 m/s - 3.50 m/s = 0.70 m/s.
Therefore, the average running rate is crucial in predicting performance in races. Knowing a runner's average speed allows us to estimate various outcomes of a race given certain distances and times.