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Homework Help: Unit conversion

  1. Jul 12, 2009 #1
    1. The problem statement, all variables and given/known data

    The acceleration of a particle is 5 m/s^2. What is the acceleration in Km/hr^2 and ft/hr^2?

    2. Relevant equations

    1km=1000m , 1m = 3.28 ft , 1hr=3600s

    3. The attempt at a solution

    ok so i have answers with calculator which is

    5m/s^2 = 64800 km/hr^2 and 212598425 ft/hr^2

    I tried doing it by showing the process but i couldnt get the same answer
    the square parts confuse me when doing the math can anyone plz show me how to do the
    process of getting those answers thanks. for example :

    5 x (1 meter / 1 second ^2 )
    5 x( ? kilometer / ? hour^2) Like that by replacing and doing the math :D .
  2. jcsd
  3. Jul 12, 2009 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Here's an example of one way to do it:
    1 m/s^2 = 1 m/(1/3600 hr)^2 = 1/(1/3600)^2 m/hr^2 = (3600)^2 m/hr^2

    Just keep replacing units by their equivalent. Here, 1 sec = 1/3600 hr. When you square a quantity, square both the number and the unit.
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