MHB Calculating Torques for Equilibrium of Truss System

AI Thread Summary
To solve the equilibrium problem for the truss system, it's essential to identify all external forces acting on the structure, specifically at points A and D. The conditions for equilibrium require that the sum of forces in both the x and y directions, as well as the sum of moments about point A, must equal zero. Calculating the moments of the external forces with respect to point A is a crucial step in determining the magnitudes of forces P and F along bars AB and AE. Additionally, it's noted that in US physics terminology, moments are often referred to as torques. Understanding these concepts is vital for maintaining equilibrium in the truss system.
paulmdrdo
Messages
89
Reaction score
2
I wonder if there's a physics person here who could help me solve this problem.

the loads applied to the truss shown in the figure cause reactions shown at A & D. A free body diagram of hinge A forms concurrent force system shown enclosed at A. Determine the magnitude of forces P & F directed respectively along bars AB & AE that maintain equilibrium of this system.
 

Attachments

  • statics2.png
    statics2.png
    5.8 KB · Views: 108
Mathematics news on Phys.org
LATEBLOOMER said:
I wonder if there's a physics person here who could help me solve this problem.

the loads applied to the truss shown in the figure cause reactions shown at A & D. A free body diagram of hinge A forms concurrent force system shown enclosed at A. Determine the magnitude of forces P & F directed respectively along bars AB & AE that maintain equilibrium of this system.

Hi LATEBLOOMER! :)

First step is to find all external forces based on the conditions for equilibrium ($\sum F_x = 0, \sum F_y = 0, \sum M_A = 0$).

Suppose the external force at A on the truss has 2 components $A_x$ and $A_y$, and similarly at D we have $D_x$ and $D_y$. Can you find these forces?
I suggest you start with calculating the moments of all external forces with respect to A.
 
I like Serena said:
I suggest you start with calculating the moments of all external forces with respect to A.

Just a comment: in US physics, at least, moments are called torques. See here and here.
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Is it possible to arrange six pencils such that each one touches the other five? If so, how? This is an adaption of a Martin Gardner puzzle only I changed it from cigarettes to pencils and left out the clues because PF folks don’t need clues. From the book “My Best Mathematical and Logic Puzzles”. Dover, 1994.
Back
Top