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# Physics/speed question

Question
Hello! How fast can an average person move their finger back and forth.  Another way of wording it would be, how fast can someone move their finger from one point to another with their hand as a stationary point.  I am not asking how fast the average person can move their arm back and forth simply because I think we can move faster with a finger (this could be an optical illusion due to the short distance a finger travels).  I have looked up the question but couldn't find an answer. If you do not know the answer any idea about how I could figure it out?
Thanks again,
concerned citizen :)

This is just a 'back of the envelope' type answer, but not being a biomechanics specialist, hear is what I have for you:

Typing is the venue I will use here - though I am sure there are studies by the video game community... Given that the average person that trains as a typist obtains a 55 words per minute average (some go much faster, but if you look around 55 seems about average for someone in a position that types a lot).  Let us assume 1 inch per key stroke (times two for the return to center line).  This gives us 6 characters per word times 55 words per minute divided by 60 seconds:

5.5 keystrokes per second.  At 2 inches of movement per keystroke, this give 11 inches per second. 11 inches = 0.28 m.  This means that a ballpark for this movement would be 0.28 m/s.

This seems reasonable this seems reasonable given that humans walk at an average of 1.4 m/s (3.1 mph).  A thought experiment is to imagine a disembodied finger puppet running to keep up to a brisk walk.

To check this though, you could just take a second to use your phone to capture video of your finger wiggling in front of a ruler.  Move the movie to your computer and then take your average distance traveled over per movement (maybe averaging over 20 back-forth movements) and the average time of the movement.  This would give you a fairly robust measurement.

Physics

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#### Dr. Jeffery Raymond

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Materials chemistry. Materials science. Spectroscopy. Polymer science. Physical Chemistry. General Physics. Technical writing. General Applied Mathematics. Nanomaterials. Optoelectronic Behavior. Science Policy.

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Teaching: General Inorganic Chemistry I & II, Organic Chemistry I & II, Physical Chemistry I, Polymeric Materials, General Physics I, Calculus I & II
My prior experience includes the United States Army and three years as a development chemist in industry. Currently I am the Assistant Director of the Laboratory for Synthetic Biological Interactions. All told, 13 years of experience in research, development and science education.

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PhD Macromolecular Science and Engineering (Photophysics/Nanomaterials Concentration), MS Materials Science, BS Chemistry and Physics, Graduate Certificate in Science Policy, AAS Chemical Technology, AAS Engineering Technology