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I Measuring Velocity

  1. May 7, 2018 #1

    I was performing some experiments about impulse and conservation of mechanical energy, and for that I was looking to good ways of measuring the velocity of a sphere under the action of a force. In free fall, having the height H it was falling along, I have used the formula v = (2gH)¹/². I'd like to know if there are more practical (experimental) way of measuring velocity of if I have to recur to indirect, mathematical ways each time.

    Thank you!
  2. jcsd
  3. May 7, 2018 #2


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    This depends on your available equipment. Stroboscopes and long exposure photos and/or video with known frame rate or good time stamping comes to mind.
  4. May 7, 2018 #3
    The idea of the camera is good, @Orodruin. I'll try that. I will also give a look about this Stroboscope. Thank you.
  5. May 7, 2018 #4


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    Absolutely agree and it all depends on the level that the OP wants to be experimenting. If the OP has a school or college lab available then there will probably be counters and light gates in a standard Physics Prep room. A TV camera with a good shutter can give timing resolution in the ms range.
    The problem with doing these experiments on your own is that nothing is very cheap and you only do each experiment once. In school, the same equipment is much better value because it can be used by several different classes every year.
    If you are happy with electronic construction, you can approach most experiments from that angle. A cheap oscilloscope can be used for accurate timing measurements. A scope can be so useful for other things too. But that would only appear to a certain type of home experimenter.
    Simulation software is a cheaper way into this topic but it may well just not appeal any more than just doing the calculations.
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