Question

A football player runs from his own goal line to the opposing team's goal line returning to the fifty yard line all i 18.0s calculate average speed and average velocity

Answer 1

assuming the pitch is 100yards long, the player runs 100yards to the other goal then a further 50 yards back to the 50-yard line. So he/she runs 150yards in 18s
150/18 = 8.33yards per second average speed.
Initial velocity = 0, average velocity =8.33
Vav = (Vinitial+Vfinal)/2
Vav = 4.16m/s

Answer 2

Answers:

Average speed = 8.33 yard/s

Average velocity = 2.78 yard/s

Explanation:

1) Definitions and equations:

i) Average speed = distance run / time elapsed

ii) Average velocity = displacement / time elapsed

iii) displacement = [final position - initial position]

2) Distance run:

i) Take a total length of 100 yards from goal to goal lines

ii) distance run = distance from goal to goal lines + back to yard 50 = 100 yards + 50 yards = 150 yards

3) Average speed = distance run / total time = 150 yards / 18.0s = 8.33 yard/s

4) Displacement:

final position - initial position = 50 yard - 0 yard = 50 yards

5) Average velocity = 50 yards / 18.0 s = 2.78 yards/s