PROBLEM 3.96
To keep a door closed, a wooden stick is wedged between the
floor and the doorknob. The stick exerts at B a 175–N force
directed along line AB. Replace that force with an equivalent
force–couple system at C.
PROBLEM 3.97
A 46–lb force F and a 2120–lb⋅in. couple
M are applied to corner A of the block
shown. Replace the given force–couple
system with an equivalent force–couple
system at corner H.
PROBLEM 3.98
A 110–N force acting in a vertical plane parallel to the yz–
plane is applied to the 220–mm–long horizontal handle AB
of a socket wrench. Replace the force with an equivalent
force–couple system at the origin O of the coordinate
system.
PROBLEM 3.99
An antenna is guyed by three cables as shown.
Knowing that the tension in cable AB is 288 lb, replace
the force exerted at A by cable AB with an equivalent
force–couple system at the center O of the base of the
antenna.
PROBLEM 3.100
An antenna is guyed by three cables as shown.
Knowing that the tension in cable AD is 270 lb, replace
the force exerted at A by cable AD with an equivalent
force–couple system at the center O of the base of the
antenna.
PROBLEM 3.101
A 3-m–long beam is subjected to a variety of loadings. (a) Replace each loading with an equivalent force–
couple system at end A of the beam. (b) Which of the loadings are equivalent?
PROBLEM 3.101 (Continued)
PROBLEM 3.102
A 3-m–long beam is loaded as shown. Determine the
loading of Prob. 3.101 that is equivalent to this loading.
PROBLEM 3.103
Determine the single equivalent force and the distance from Point A to its line of action for the beam and
loading of (a) Prob. 3.101a, (b) Prob. 3.101b, (c) Prob. 3.102.
PROBLEM 3.104
Five separate force–couple systems act at the corners of a piece of sheet metal, which has been bent into
the shape shown. Determine which of these systems is equivalent to a force F = (10 lb)i and a couple of
moment M = (15 lb ⋅ ft)j + (15 lb ⋅ ft)k located at the origin.
PROBLEM 3.105
The weights of two children sitting at ends A and B of a
seesaw are 84 lb and 64 lb, respectively. Where should a
third child sit so that the resultant of the weights of the
three children will pass through C if she weighs (a) 60 lb,
(b) 52 lb.