F2
F1
ma
gc
(2000lbm × 2ft sec2) ÷ 32.17
ft lbm
lbf sec2
124 lbf
FORCE EQUILIBRIUM
Application of Newton's Laws
CP-04
Page 16
Rev. 0
Force Equilibrium Summary
+
The force that is the resultant force of all forces acting on a body is defined as
the net force.
+
If the vector sum of all the forces acting on an object is equal to zero, then the
object is in equilibrium.
+
The first condition of equilibrium is stated as follows: "A body will be in
translational equilibrium if and only if the vector sum of forces exerted on a
body by the environment equals zero."
F + F + F = 0
1
2
3
or
'
F = 0
+
Any force or system of forces capable of balancing a system so that the net
force is zero is defined as an equilibrant.
c.
Since the car remains on the surface, forces N and W are in equal and
opposite directions. Force F must be applied in an equal and opposite
2
direction to F in order for the forces to be in equilibrium.
1
Summary
The concepts presented in this chapter are summarized below.
