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Homework Help: Motion Help

  1. Nov 9, 2004 #1
    Hi, i have a few questions about motion. any help would be much appreciated.

    Q1. If a car was driven 250km from home to town, and back again in 12 hours:
    a) what was the average velocity?
    b) what was the average speed?
    c) what was the average speed in m/s?
    (show working out)


    thats it for now...thanks to any helpers, incase i dont reply. :smile:
     
  2. jcsd
  3. Nov 9, 2004 #2

    ek

    User Avatar

    Do you know the difference between speed and velocity?

    Because that concept is pretty germane to these questions.
     
  4. Nov 9, 2004 #3
    Hints:
    a) There is no overall displacement.
    b) The total distance traversed is 250 km x 2 = 500 km
    c) 1 km = 1000 m. 1 hour = 3600 seconds. For example, if you want to convert 100 km/h to m/s, you would proceed as follows:

    100 km = 100,000m
    1 hour = 3600 seconds. So,
    100 km/h = 100,000m/3600 s = 27.78 m/s
     
  5. Nov 10, 2004 #4
    a) average velocity=total displacement/time
    b) average speed=total distance/time
    c) 1km=1000m, 1h=3600s
    1km/h=1000/3600 m/s

    I thinks these hints are pretty straight forward...try it yourself... :smile:
     
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