Homework Help

Walking on pebbles in bare feet is more painful than walking on sand. Why?

user profile pic

syedajmain | Student | eNoter

Posted December 22, 2009 at 12:15 PM via web

dislike -1 like

Walking on pebbles in bare feet is more painful than walking on sand. Why?

Tagged with physic, physics, science

1 Answer | Add Yours

user profile pic

pohnpei397 | College Teacher | (Level 3) Distinguished Educator

Posted December 22, 2009 at 12:24 PM (Answer #1)

dislike 1 like

This is because of the amount of force that is put on your foot and the area over which the force is applied.  Since pressure = force/area, the same force on a smaller area means more pressure.

When you are walking on sand, the force being applied by your body is spread out over the entire surface of your foot.  Therefore, there is relatively little pressure on any one point (since pressure = force/area).

When you step on a pebble it is an entirely different story.  Instead of spreading the pressure over your whole foot, much more of the pressure is applied to the small area that is actually touching the pebble.

So, more pressure applied on a given area of your foot causes more pain.

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes