Normal Force: When is mg not Enough?

AI Thread Summary
The normal force is not always equal to mg; it varies based on the situation and the forces acting on the object. It is defined as the force exerted by a surface perpendicular to the object in contact with it. The direction of the normal force can be upward or downward, depending on the orientation of the objects involved. To determine the normal force in different scenarios, applying Newton's 2nd law is essential. Understanding the context of the contact between objects is crucial for accurately calculating the normal force.
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In which cases is the normal force acting on an object simply mg, and in which cases is it something else? If it's not mg, how can I figure out what it is?
 
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the normal force depends on the situation. but you will always need to use Newton's 2nd law.
 
ok, so I don't really understand what the normal force is. By what is it exerted, by the ground? and it's not always upward, correct? it's perpendicular to the object, I think.
 
you have normal when you have two objects that have contact. the direction is perpendicular to the contact surface. upwards or downwards will depend on which object you are referring.
 
Ok, I got it, thank you.
 

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