Free Body Diagram Solve Problem: Find Force Normal

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leprofece
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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?
 
Attachments
  • Textbook figure of a window washer pushing a scrub brush up a vertical window at constant speed by applying a force F at an angle to the wall, with the brush weight W labelled.
    Dibujo.JPG
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  • Physics diagram of a ladder leaning against a wall at an angle, with a force F applied at the top along the ladder and the ladder's angle to the horizontal labeled 53.1 degrees.
    Dibujo2.JPG
    2.7 KB · Views: 158
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
 
Attachments
  • Handwritten free-body diagram on paper with a horizontal line and labeled arrows for FN, F applied, FR (friction force), and mg, plus Horizontal and Vertical axis labels, and equations for sum of Fx and sum of Fy with Fx and Fr terms.
    images2.1.jpg
    86.6 KB · Views: 144
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