Free Body Diagram Solve Problem: Find Force Normal

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Discussion Overview

The discussion revolves around solving a physics problem involving free body diagrams, specifically focusing on the normal force and its relationship with other forces acting on an object. Participants explore the components of forces in both the x and y directions, as well as the implications of a given angle in the context of the problem.

Discussion Character

  • Technical explanation, Debate/contested, Mathematical reasoning

Main Points Raised

  • One participant requests a free body diagram and references a textbook solution involving the normal force expressed as \( n = f \cos x \) and a vertical component equation \( f \sin x = w + \mu N \).
  • Another participant emphasizes the importance of clarity in the question and suggests drawing a free body diagram to analyze forces in the x and y directions, providing equations for both directions.
  • A later reply seeks clarification on the free body diagram and reiterates the need to break down the applied force into its x and y components, while also considering gravity and friction.
  • One participant expresses a desire for a drawing of the free body diagram and indicates a disagreement regarding the placement of the frictional force in the x-axis.
  • Another participant questions the definition of "Fr" and asserts that their interpretation aligns with the equations presented, suggesting that the disagreement may stem from different variable notations for the same forces.
  • It is noted that the equations presented by different participants are in agreement despite the use of different symbols for forces.

Areas of Agreement / Disagreement

Participants express differing views on the placement of the frictional force in the free body diagram, with some asserting it is vertical while others argue it should be horizontal. There is no consensus on this aspect of the problem.

Contextual Notes

Participants have not fully resolved the definitions and roles of the forces involved, particularly regarding the frictional force and its representation in the free body diagram. The discussion reflects varying interpretations of the problem setup and the corresponding equations.

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SOLVE THIS PROBLEM View attachment 3071
And this is the figure View attachment 3072

I need the free body diagram because the book solve this problem in this way
the force normsl is n = fcosx
the verticall componente is fsenx = w + miuN
why does the fr is vertical in this case?
 

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It'd be more helpful if you were more clear with your question...or fix the typo's in your sentence.

We have to look at the forces in the $x$ and $y$ direction, which you can find by drawing a free-body diagram.

Acting in the $x$ direction, we have the force of normal, and the force applied by the brush in the $x$ direction.
$$F_x=F_{bx}-F_N$$
$$=F(\cos\left({53.1^{\circ}}\right)-F_N=0$$

Similarly for $y$:
$$F_y=F_{by}-F_f-F_g$$
$$=F(\sin\left({53.1^{\circ}}\right))-F_f-F_g$$

What is your question again? :confused:

EDIT: It seems as though you want clarification of the free-body diagram. The window washer applies a force on the brush that is $53.1$ degrees from the horizontal, which we can break into its constituent $x$ and $y$ vectors. We also have the force of gravity acting downwards, and because the brush is pushed against the wall, we also have the force of normal and friction.
 
Last edited:
Rido12 said:
It'd be more helpful if you were more clear with your question...or fix the typo's in your sentence.

We have to look at the forces in the $x$ and $y$ direction, which you can find by drawing a free-body diagram.

Acting in the $x$ direction, we have the force of normal, and the force applied by the brush in the $x$ direction.
$$F_x=F_{bx}-F_N$$
$$=F(\cos\left({53.1^{\circ}}\right)-F_N=0$$

Similarly for $y$:
$$F_y=F_{by}-F_f-F_g$$
$$=F(\sin\left({53.1^{\circ}}\right))-F_f-F_g$$

What is your question again? :confused:

EDIT: It seems as though you want clarification of the free-body diagram. The window washer applies a force on the brush that is $53.1$ degrees from the horizontal, which we can break into its constituent $x$ and $y$ vectors. We also have the force of gravity acting downwards, and because the brush is pushed against the wall, we also have the force of normal and friction.

Yeah I want the drawing or the plot of the free body diagram of the problem That is I required or asked
 
Okay! What do you have on your free body diagram so far? :confused:
 
\partial \nabla

Here you are my free body diagram as you see we disagree in x axe because you have f cos53 - fr

The book says that fr must be in the vertical
accordin to book in the horizontal there is only one force f cos53 View attachment 3117
 

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What are you defining "Fr" to be?

Your textbook isn't in disagreement to what I've said.

I said:

$F_x=F_{bx}-F_N$

$F_x$= zero:

$F(\cos\left({53.1^{\circ}}\right)-F_N=0$

So it simplifies to:

$F_N=F(\cos\left({53.1^{\circ}}\right))$

That is what you have in your first post.

I think you are referring to frictional force with $F_r$. I used $F_f$ instead. Your free body looks correct, and our equations are in agreement. We just used different variables :D
 

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