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Homework Help: Find acceleration on planet x given mass, time, height.

  1. Jan 15, 2012 #1
    1. The problem statement, all variables and given/known data

    It’s your lucky day! You have been chosen by NASA to be the astronaut for its first
    intergalactic expedition. In your excitement for the mission, however, you forgot to read
    the road map and you have no idea where your spacecraft landed. Your intimate
    knowledge of physics will save the day since you have a detailed database of the
    acceleration due to gravity for all known planets in the universe. Stepping out of your
    Mark 98-Q Ultratrav ion-drive spacecraft, you drop a 10 kg tool box from a 2 m height
    and note that it takes 1.4 seconds to reach the ground. What is the acceleration due to
    gravity on this planet?

    2. Relevant equations


    3. The attempt at a solution

    I used v=(h_0-h_f)/(delta_t), got v=1.43 m/s. I'm not sure how to proceed from here.
  2. jcsd
  3. Jan 15, 2012 #2
    If I asked you to calculate how long it takes for a toolbox on Earth to fall 2m could you come up with the right time?

    Write down that formula here and you are on your way to solving this problem.
  4. Jan 15, 2012 #3
    you are given distance and time, you are asked to find acceleration. Therefore, you should use gailleos equation
  5. Jan 16, 2012 #4


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    Hello chuck_stone. Welcome to Pf !

    What you calculated was the average velocity of the toolbox while it was falling. If it starts from rest, what its velocity the moment before it touches ground?
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