9. Olympic gold medalist Michael Johnson runs one time around the track - 400 meters - in 38 seconds. What is his displacement? What is his average velocity?
10. If an object is moving eastward and slowing down, then the direction of its velocity vector is .
a. eastward
b. westward
c. neither
d. not enough info to tell
11. If an object is moving eastward and slowing down, then the direction of its acceleration vector is .
a. eastward
b. westward
c. neither
d. not enough info to tell
12. Which one of the following quantities is NOT a vector?
a. 10 mi/hr, east
b. 10 mi/hr/sec, west
c. 35 m/s, north
d. 20 m/s
13. Which one of the following quantities is NOT a speed?
a. 10 mi/hr
b. 10 mi/hr/sec
c. 35 m/s
d. 20 m/s
14. Which one of the following statements is NOT true of a free-falling object? An object in a state of free fall .
a. falls with a constant speed of -10 m/s.
b. falls with an acceleration of -10 m/s/s.
c. falls under the sole influence of gravity.
d. falls with downward acceleration which has a constant magnitude.
15. The average speed of an object which moves 10 kilometers (km) in 30 minutes is .
a. 10 km/hr
b. 20 km/hr
c. 30 km/hr
d. more than 30 km/hr
Answers: 1
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9. Olympic gold medalist Michael Johnson runs one time around the track - 400 meters - in 38 seconds...
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