A chair of mass 15.0 is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force = 37.0 that is directed at an angle of 43.0below the horizontal and the chair slides along the floor.

Question

A chair of mass 15.0 is sitting on the horizontal floor; the floor is not frictionless. You push on the chair with a force  = 37.0 that is directed at an angle of 43.0below the horizontal and the chair slides along the floor.

anonymous · Answer

what are you asking

anonymous · Answer

Oh sorry.  I'm looking for the Normal force that the floor exerts on the chair.  Am I supposed to set up the reference frame with respect to the floor?  I don't know how to do that if I only have info for the chair.

anonymous · Answer

normal force is the force trying to maintain the chair at its vertical position instead of falling down. 

i.e., total downward force is balanced by the Normal force.
step 1) You have to draw the free body diagram

anonymous · Answer

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That's it.

anonymous · Answer

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anonymous · Answer

$$\sum F_x=ma_x=F_x=F_f$$
$$\sum F_y=ma_y=N-mg-F_y$$

anonymous · Answer

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