Calculate the tension in the tie-rope between the rod and the wall

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AI Thread Summary
The discussion focuses on calculating the tension in a tie-rope supporting a 250-kg block via a pivoting rod of 100 kg. Participants analyze the forces acting on the system, questioning the initial assumptions about the forces and torques involved. Key equations for horizontal and vertical forces are presented, with emphasis on the need to consider torque balance at the pivot point. Clarifications are made regarding the relationship between tension and gravitational forces acting on the block and rod. The conversation highlights the importance of equilibrium in solving the problem accurately.
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Homework Statement


Hi again ,, My third Question of the day :
A 250-kg block is supported by a cable attached to a rod of mass 100 kg that can pivot
at the base.
a) Calculate the tension in the tie-rope between the rod and the
wall if it is holding the system in the position shown in Figure.
b) Find the horizontal and vertical forces exerted on the base of
the rod.


Homework Equations





The Attempt at a Solution


in the attachment you'll see the forces I assigned to the system ,, is it right ?? or should I have T2 (above mg) ?? if not I think the question will be too easy:
Fnet(x)=Fh-Tcos(20)
Fnet(y)=Fv+Tsin(20)-mg-Mg (but Tsin(20) = mg) so i can get T and Fv and Fh without even using the Torque ,, so any ideas ??
 

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Lord Dark said:
in the attachment you'll see the forces I assigned to the system ,, is it right ??

Where is the force which is acting along the rod? What balances T(cos 20) in your first diagram?
 
Consider the sum of the torques about the pivot.

Equilibrium means that they balance.
 
Shooting Star said:
Where is the force which is acting along the rod? What balances T(cos 20) in your first diagram?

you mean mg ??

LowlyPion said:
Consider the sum of the torques about the pivot.

Equilibrium means that they balance.

yea I got it ,, i thought at first that T(sin20) = mg but now i know what is my mistake ,, thanks guys
 
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