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Homework Help: Work done while walking!

  1. Jan 3, 2007 #1
    Hi all,

    Work,in terms of Physics, is defined as F.d i.e scalar product of Force & displacement.My query is "While walking are is some work is done by our body if no external force is applied on our body?.Is some work is being done by the internal energy supplied by our body?.Thanks.
  2. jcsd
  3. Jan 4, 2007 #2
    do you mean "is any work done while walking?"
    the answer is definitely yes. You push the earth so that the earth pushes you while working. The energy goes into frictional heat, kinetic energy of the earth, of your body, and the gravitational potential you build up when lifting you, also electrostatic potential between the ground and you... and many many more...

    also, if you look at the muscles cells of the body, they contract and relax during walking, which requires chemical energy from ATPs and many others things.
  4. Jan 4, 2007 #3


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    Staff: Mentor

    Well. I'll need to be scientifically detached here for several reasons. Sigh.

    To the original post/poster (OP) -- what are the differences between a human female walking versus a cylinder rolling or a mass sliding on a frictionless plane?

    Sigh again. Anybody want to work out?
  5. Jan 4, 2007 #4
    yes, I meant while walking, is some work is being done in terms of 'F.d'?If yes,how the force 'F' will be calculated?.If someone travels 5m what would be the work done in terms of definition of work i.e,

  6. Jan 5, 2007 #5


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    Staff: Mentor

    As I was hinting, walking is less efficient than rolling. Why is it less efficient? What percentage of our leg motions are actually propelling us forward? What do you have to do with your arms to stay balanced? Does swinging your ams produce useful work in walking?
  7. Jan 5, 2007 #6


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    Staff Emeritus
    Science Advisor
    Gold Member

    Use the work-energy theorem. If you walk at constant speed over some distance, what is the net work done on you?
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