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Homework Help: Time vs Height of a freefalling object. Please help me!

  1. Nov 30, 2005 #1
    Just a quick question to start. It's really urgent as has to be handed in tomorrow (Thursday).
    I have conducted an investigation involving the acceleration of a mass attached to ticker-tape.
    I have drawn a Time vs Height graph, which generally shows that as time doubles, height quadrouples as expected.
    However, I am confused about my first reading. It seems anomolous, but both of two readings are almost the same, so surely not!
    Here is the graph:
    http://img393.imageshack.us/img393/3083/scr3fn.gif [Broken]
    It's the first point in question. Why is the height so high? Is it because air resistance has not yet had effect? Or do you think it could have been a problem with the experiment setup (tickertape)?
    Any input would be really, really appreciated - thanks in advance for your time.
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Nov 30, 2005 #2


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    I have more concerns for your data then just the first point. The way I have seen this experiment done is to drop the mass attached to the wax tape while a 60Hz spark marks the tape. The data consists of marks representing equal divisions of time separated by increasing distance. Your data appears to show equal increments in distance separated by a varying time interval?

    You need to describe your data collection methods.
  4. Nov 30, 2005 #3

    Hello Integral, and thanks for your reply.

    Yes, the ticker-timer marks the dots on the tape every 0.2s. However, the input variable for this investigation was height as oppose to time, so I measured the height along the ticker-tape.

    I know by convention the input variable would be plotted along the x axis, but in this case I decided not to so the gradient could be used to find the acceleration.

    I'm pretty sure now that the anomoly was just an anomoly, probably due to bad equipment or setup.

  5. Nov 30, 2005 #4


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    Your data plot is incorrect. It does not reflect the .2s time increment. You have plotted a .2m increment in distance. I would recommend that you reexamin your data and attempt to plot it correctly.
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