Question

8. A person starts at a position of 25 meters and finishes at a position of 2 meters. The trip takes
4.5 seconds. What is the person's average velocity? What is the person’s average speed?
9. A person starts at a position of 2 meters and finishes at a position of 25 meters. The trip takes
4.5 seconds. What is the person's average velocity? What is the person’s average speed?
10. A train travels at a speed of 30 m/s. The train starts at an initial position of 1000 meters and
travels for 30 seconds. What is its final position?
11. At a time of 30 seconds a runner passes a distance marker labeled "125 meters." If the
velocity of the runner is +5.0 m/s, when did the runner pass the distance marker for 75
meters?

Answer 1

#8,9) speed is distance/time, so (25-2)m/4.5s = ____ m/s
The velocity also has a sign, depending on whether the distance decreased or increased
#10) since distance = speed * time, that would be 1000 + 30*30 = ____ m
#11) 30 + (125-75)/5 = ___s
This sounds like positive direction is toward the finish line, so the markers are decreasing.