Is Work Done While Walking Without External Force Applied?

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Work is defined in physics as the product of force and displacement, and during walking, internal energy from the body contributes to work done. When a person walks, they exert force on the ground, which in turn propels them forward, resulting in various forms of energy transfer, including kinetic and potential energy. The efficiency of walking is questioned, with comparisons made to rolling or sliding, highlighting that not all leg motions effectively propel the body forward. The discussion also touches on the calculation of work done while walking, emphasizing the importance of understanding force and displacement in this context. Overall, walking involves significant internal work despite the absence of external forces.
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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.
 
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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.
 
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?
 
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,

w=F.d.
 
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?
 
shehri said:
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,

w=F.d.
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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