Question

If Graham walks 4.2 m to the right over 2.1 s and then 5.0 m back to the left over the next 4.1s, what is his average velocity over the whole process?

a. 2.1 m/s
b. 4.2 m/s
c. 9.2 m/s
d. -0.13 m/s
e. 26 m/s

Answer 1

Graham's average velocity over the entire walk is -0.129 m/s, which indicates he ends up moving towards the left overall.

Step-by-step explanation:

To find Graham's average velocity over the entire walk, it's necessary to consider his total displacement and the total time taken. Graham walks 4.2 m to the right and then 5.0 m back to the left. His total displacement is therefore 4.2 m - 5.0 m = -0.8 m (since displacement includes direction, and to the left is considered the negative direction). The total time taken for both segments of the walk is 2.1 s + 4.1 s = 6.2 s.

The average velocity can be found by dividing the total displacement by the total time: Average velocity = Total displacement / Total time = -0.8 m / 6.2 s = -0.129 m/s (which can be rounded to -0.13 m/s for significant figures).

The negative sign indicates that the direction of the average velocity is to the left.