‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
‫ آﻗﺎي دﻛﺘﺮ اﺑﻮاﻟﻔﺘﺤﻲ‬: ‫ﻣﺪرس‬
‫ راﻣﻴﻦ اﻣﻴﺪوار‬:‫ﺗﺪرﻳﺲ ﻳﺎر‬
‫درس اﺳﺘﺎﺗﻴﻚ – راه ﺣﻞ ﺗﻤﺮﻳﻦ ﺳﺮي ﻫﻔﺘﻢ‬
1. Determine the torque M that can be resisted by the band brake if a force P is applied to the handle of the lever.
The coefficient of static friction between the belt and the wheel is μs. The wheel is pin-connected at its center, B
P = 30 N
μ s = 0.3
r = 400 mm
a = 200 mm
b = 750 mm
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
2. The spool of wire having a mass M rests on the ground at A and against the wall at B. Determine the forces
acting on the spool at A and B for the given force P. The coefficient of static friction between the spool and the
ground at point A is μs. The wall at B is smooth. Check the no-slip assumption is good or not.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
3.. The system of two blocks, cable, and fixed pulley is initially at rest. Determine the horizontal force P necessary
to cause motion when (a) P is applied
pplied to the 55-kg block and (b) P is applied to the 10-kg
kg block. Determine the
corresponding tension T in the cable for each case.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
4. A cable is attached to the plate B of mass MB, passes over a fixed peg at C, and is attached to the block at A.
Using the coefficients of static friction shown, determine the smallest mass of block A so that it will prevent sliding
motion of B down the plane.
MB = 20 kg μA = 0.2
θ = 30 deg μB = 0.3
g = 9.81 m/s2
μC = 0.3
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
5. The car has a mass of 1.6 Mg and center of mass at G. If the coefficient of static friction between the shoulder
of the road and the tires is μs = 0.4. determine the greatest slope θ the shoulder can have without causing the car
to slip (‫ )ﻟﻐﺰﻳﺪن‬or tip over(‫ )ﭼﭗ ﺷﺪن‬if the car travels along the shoulder at constant velocity.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
6. A 35-kg disk rests on an inclined surface for which μr =0.2. Determine the maximum ver9cal force P that may be
applied to link AB without causing the disk to slip at C.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
7. The semicylinder of mass m and radius r lies on the rough inclined plane for which φ = 10 deg and the
coefficient of static friction is μs = 0.3. Determine if the semicylinder slides down the plane, and if not, find the
angle of tip θ of its base AB.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
8. The uniform 60-kg crate C rests uniformly on a 10-kg dolly D. If the front casters of the dolly at A are locked to
prevent rolling while the casters at B are free to roll, determine the maximum force P that may be applied without
causing motion of the crate. The coefficient of static friction between casters and the floor is μs = 0.35 and
between the dolly and the crate, μd = 0.5.
‫ داﻧﺸﻜﺪه ﻣﻬﻨﺪﺳﻲ ﭘﺰﺷﻜﻲ‬- ‫درس اﺳﺘﺎﺗﻴﻚ‬
1391-1390 ‫ﻧﻴﻤﺴﺎل دوم‬
9. Determine the maximum and the minimum values of weight W which may be applied without causing the 50-lb
block to slip. The coefficient of static friction between the block and the plane is μs = 0.2 and between the rope
and the drum D μd = 0.3