For a body to be in equilibrium under the combined action of several forces.

Question

a) all the forces must be applied at the same point
b) all of the forces form pairs of equal and opposite forces
c) the sum of the components of all the forces in any direction must equal zero
d) any two of these forces must be balance by a third
e) the lines of action of all forces must pass through the center of gravity

work (c)
A particle is in equilibrium if the resultant force acting upon it is zero. A rigid body is in equilibrium if the resultant force is zero and if the resultant moment = 0. Thus Fx=0 and Fy=0

For a body to be in equilibrium under the combined actions of several forces:
a) all the forces must be applied at the same point
b) all of the forces form pairs of equal and opposite forces
c) any two of these forces must be balance by a third
d) the sum of the torques about any point must be zero
e) the lines of action of all the forces must pass through the center of gravity of a body.

work (d)
The sum of the net forces must be zero as well as the moments around any point must be zero for a body to be in equilibrium

thanks

For a body to be in equilibrium under the combined action of several forces.
a) all the forces must be applied at the same point
b) all of the forces form pairs of equal and opposite forces
c) the sum of the components of all the forces in any direction must equal zero
d) any two of these forces must be balance by a third
e) the lines of action of all forces must pass through the center of gravity

work (c)
***That is probably the best answer, but it is wrong. For a body to be in equilibrium, the sum of the forces in any direction must equal zero, AND the sum of the moments about any point have to be zero.****
A particle is in equilibrium if the resultant force acting upon it is zero. A rigid body is in equilibrium if the resultant force is zero and if the resultant moment = 0. Thus Fx=0 and Fy=0

For a body to be in equilibrium under the combined actions of several forces:
a) all the forces must be applied at the same point
b) all of the forces form pairs of equal and opposite forces
c) any two of these forces must be balance by a third
d) the sum of the torques about any point must be zero
e) the lines of action of all the forces must pass through the center of gravity of a body.

work (d)
The sum of the net forces must be zero as well as the moments around any point must be zero for a body to be in equilibrium
***again, the is the best answer, but it is incomplete. See above. YOur comments on each tells me You understand the concept of equilibirium: all forces adding to zero, and the sum of moments about any point adding to zero.

so the answers I choose were right.

Answer 1

Yes, the answers you chose were correct. However, you need to make sure that you understand the concept of equilibrium and that you can explain it in your own words.