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Simple question, can you answer ? ?

  1. Feb 22, 2006 #1
    simple question, can you answer ...??!!!??!!!

    Ok, all you physics whizzes out there, im usually quite good at physics, and im in the middle of something, its some crappy motion and acceleration work.

    Starting with s=ut + 1/2 at^2

    In this experiment im dropping the objuect, so obviously u = 0, s = displacement, which in this case ive got a range of values for. t = time, which again i have a range of values for., this leaves me with calculating a, all seems fine, but as a sidenote, the teacher has put, "a = g", so what is g

    ive never heard of a g in this kind of topic. Its not gravity, cos im suposed to be working it out, lol, gravitational field strength is a constant at 9.81, so its not that.

    and also, im getting rusty at this, does a correspond to finish speed or end speed, or is it something completely different like acceleration???

    Thanks for the help, dragon2309
  2. jcsd
  3. Feb 22, 2006 #2
    Hi, sounds like thats exactly what your supposed to measuring.

    That is, the puporse of your experiment is to determine g, which is the "a" in the kinematic eqn you quoted.

  4. Feb 22, 2006 #3


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    Staff: Mentor

    Well if you are dropping something, what do you suppose the acceleration will be due to? The teacher has put "a = g" for a reason. It sounds like your instructor wants you to experimentally calculate the acceleration, to see how close you can get to the generally accepted value that you listed.

    BTW, homework questions should be posted in the homework forums here in PF. Welcome to PF!
  5. Feb 22, 2006 #4
    Yes, it is, i do have to find g, but why is it called g, and what is it, is it acceleration??

    Thanyou, dragon2309

    *EDIT* - sorry for posting twice, i read your rules and saw that questions like this should go in the homework forum, sorry again
  6. Feb 22, 2006 #5
    Oh and yes, "a" is indeed acceleration.

    Whilst you are measuring it you can expect to get a range of values. Once you have averaged them u can compare them with the "accepted value of g, ie. 9.81....

  7. Feb 22, 2006 #6
    Wow, that was a fast set of replies, thank you everyone for your help, i can now get on and write the paper up now, i wasnt gonna do it and then find out that a was actually something wierd, thanks again!!!

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