Chapter SH, Problem 2.7APP

To determine

To Calculate: The change in speed of the runner.

Answer to Problem 2.7APP

The change in speed of the runner is $\text{3}\text{.0 m/s}$ .

Explanation of Solution

Given data:

The speed of the runner at halfway $=4\text{ m/s}$

The speed of the runner in the last stretch $=7\text{ m/s}$

Formula used:

Change in speed $=\text{final speed}-\text{initial}\text{}\text{ speed}$

Calculation:

As per the problem,

Initial speed $=4\text{ m/s}$

Final speed $=7\text{ m/s}$

Therefore,

Change in speed $=7\text{ m/s}-4\text{ m/s}=\text{3 m/s}$

Conclusion:

The change in speed of the runner is $\text{3}\text{.0 m/s}$ .