‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
‫ آﻗﺎي دﻛﺘﺮ اﺑﻮاﻟﻔﺘﺤﻲ‬: ‫ﻣﺪرس‬
‫ راﻣﻴﻦ اﻣﻴﺪوار‬:‫ﺗﺪرﻳﺲ ﻳﺎر‬
‫درس اﺳﺘﺎﺗﻴﻚ – راه ﺣﻞ ﺗﻤﺮﻳﻦ ﺳﺮي اول‬
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1. Determine the magnitude of the resultant force FR = F1 + F2 and its direction, measured
counterclockwise from the positive w axis.
F1 = 250 N
F2 = 500 N
Θ1 = 30 deg
Θ2 = 30 deg
Θ3 = 45 deg
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
2. A resultant force F is necessary to hold the ballon in place. Resolve this force into components along
the tether lines AB and AC, and compute the magnitude of each component.1 70 deg
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
3. The cable exerts a tension of 2 kN on the fixed bracket at A. Write the vector expression for tension
T
4. Determine the magnitude of force F so that the resultant FR of the three forces is as small as
possible. What is the minimum magnitude of FR?
F1 5 kN
F2 4 kN
30 deg
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
tensi in the chain is
5. The access door is held in the 30o open position by the chain AB. If the tension
100 N, determine the projection of tension force onto the diagonal axis CD of the door.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
Replace the three forces which act on the bent bar by a force
force-couple
couple system at the support point A. Then
determine the x-intercept of thee line of action of the stand
stand-alone resultant force R.
7. Determine the moment of the force F about the Oa axis. Express the result as a Cartesian vector.
 50 


F =  − 20  N
 20 


a=6m
b=2m
c=1m
d=3m
e=4m
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
8. The curved rod lies in the x-y plane and has radius r. If a force F acts at its end as shown, determine the moment of
this force about point O.
r 3m
a 1m
b 2m
45 deg
F 80 N
9. Three couples are formed by the three pairs of equal and opposite forces. Determine the resultant M of the three
couples.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
10. The trap door OA is raised by the cable AB which passes over the small guide pulleys at B. The tension everywhere
in the cable is T, and this tension applied at A causes a moment Mo about the hinge at O. Plot the quantity Mo/T , which
is the moment arm relative to O of the tension applied at A, as a function of the door angle θ for the range 0 ≤ θ ≤ 90.
Determine the maximum and minimum values of the moment arm over this range of θ.