Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Forces while walking and driving

  1. Feb 12, 2010 #1
    i am confused about the exact forces in play while we walk and while a car is driven, can anybody plz show me a free body diagram regarding these with explanation? Also, which force does work when we walk?

  2. jcsd
  3. Feb 13, 2010 #2


    User Avatar
    Science Advisor
    Homework Helper

    Welcome to PF!

    Hi troy611! Welcome to PF! :wink:
    Friction against the ground, in both cases.

    (plus, in normal walking mode, though not essential, falling very slightly onto each succeeding step)
    You tell us … how is work done defined? :smile:
  4. Feb 14, 2010 #3
    The knee is always slightly flexed when walking. Also there are three fulcrum in human body as a machine, ankle joint, knee joint and hip joint. the pelvis also rotates in an important way. In a car wheel there is only one fulcrum traditionaly believed to be the hub. I have my own idea where the fulcrum should be. To me the hub is actually the load arm, axel effort and tire circumference the fulcrum. This observation though is not so popular
  5. Feb 15, 2010 #4
    ohk...thanks everyone for helping out
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook