# data[].attributes.body
Method of joints: when all member forces are desired.
Method of sections: when only a few member forces are desired.
Combination: when truss contains lots of joints, start with method of sections.

# data[].attributes.body
Solve using a system of 2 equations and the known sum of the forces being equal to 0. Forces in the x-direction and forces in the y-direction.

# data[].attributes.body
How to analyze a 2-D truss structure?

# data[].attributes.body
Members with F = 0. When there are 3 members and only two are aligned, the nonaligned member carries no force. When there are 2 members and they are not aligned, they each carry no force.

# data[].attributes.body
In the FBD tension is drawn as an arrow pointing away from the center, whereas compression is an arrow pointing towards the center. It is drawn this way so you know at the end if the force is tension or compression based on the sign. If you get a negative answer it means you drew the force in the wrong direction in the FBD.

# data[].attributes.body
A truss is determinate if the number of unknowns equals the number of equations present. The number of equations can be found by determining the number of joints present and multiplying that number by 2. The number of unknowns is found by adding the number of members plus the number of reactions. If equations outnumber the unknowns, it is partial fixity. If the number of unknowns equals the number of equations, the truss is statically determinate if full fixity. If unknowns outnumber equations present, it is statically indeterminate.

# data[].attributes.body
Choose a section that gives 3 unknowns since we only have 3 equations.

# data[].attributes.body
This method is related to the prior concepts of static equilibrium, free body diagrams, and moments. Steps: make a cut, draw FBD of one of the sections, solve the 2D equilibrium problem.

# data[].attributes.body
This method is related to the prior concepts of static equilibrium and free body diagrams. Start with the joint connected to 3 forces.

# data[].attributes.body
Think about which way it can and can't move, if it can't move in a certain direction there is a reaction force there.

We calculate the reactions by utilizing equilibrium equations along each axis.

# data[].attributes.body
Rigid-Body Equilibrium has a moment, unlike Particle equilibrium. 3 equations. Forces in the x and y-direction along with a moment in the z-direction.

Moment = Force x Distance (shortest distance from a point to force's line of action)