My weight cancels out the normal force from the floor

AI Thread Summary
When standing and leaning against a wall, two main forces act on a person: the normal force from the ground counteracts gravity, while friction prevents slipping. The force exerted by the wall is balanced by the horizontal frictional force at the feet, ensuring stability. The vertical component of the forces includes gravity acting downward and the normal force acting upward. Additionally, while the vertical friction force at the wall is typically disregarded, it can play a role in preventing sliding. Understanding these forces is crucial for analyzing equilibrium in this scenario.
PhysKid24
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If I'm standing on the ground and at the same time leaning on a wall, what are the forces acting on me? My weight cancels out the normal force from the floor, but what cancels out the force exerted on me by the wall, say horizontally, so as to make the sum of the forces 0? Thanks.
 
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PhysKid24 said:
If I'm standing on the ground and at the same time leaning on a wall, what are the forces acting on me? My weight cancels out the normal force from the floor, but what cancels out the force exerted on me by the wall, say horizontally, so as to make the sum of the forces 0? Thanks.


In your feet you have two reaction forces. One normal force because you are standing on the ground (due to gravity) and one that is directed horizontally in the opposite direction (towards the origin of the reference frame if you will) because of friction between your shoes and the ground. Otherwise, you would fall over. Then in your center of mass you have gravity working in onto you. At the point where you touch the wall you will have two reactionforces again. One horizontal (otherwise you would breake the wall and fall through it) and one force pointed upwards due to friction. Otherwise you would slide down...

regards
marlon
 
Normally the vertical friction force at the wall is disregarded...

marlon, just as an addendum
 
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