What is the static friction force acting on the object?

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The static friction force acting on an object is determined by the coefficient of static friction and the normal force. In this case, with a coefficient of static friction of 0.5 and a normal force of 10N, the maximum static friction force is calculated to be 5N. However, when a horizontal force of 2N is applied, the static friction force only needs to match this applied force to keep the object at rest. Therefore, the static friction force is 2N, not the maximum of 5N. The key point is that static friction adjusts to the applied force, up to its maximum limit.
unknown physicist
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Homework Statement


A block sitting on a flat surface has a us of 0.5. The normal force acting on the block is 10N. If someone pushes the block with a horizontal force of 2N. What is the static friction force acting on the object?

Homework Equations


F=ma
fs=usR (less than or equal to)

The Attempt at a Solution


I said that since the coefficient of static friction is 0.5, therefore if we multiply it by 10N then we will get 5N, and that is force of static friction. However the answer is incorrect and the correct answer is 2N. Why is that? Isn't 2N the applied force?
 
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unknown physicist said:
therefore if we multiply it by 10N then we will get 5N, and that is force of static friction
It is the "maximum" possible force of static friction.
Also, how can the frictional force be more than the applied force when the object is at rest?
 
unknown physicist said:
fs=usR (less than or equal to)
Did you not understand the significance of the "less than or equal to" rider?
 
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