د مایعاتو احصایې - ستونزې او حل لارې
Liquid pressure
1. What is the difference between the hydrostatic pressure of blood between the brain and the soles of the feet of a person whose height 165 cm (suppose the کثافت of blood = 1.0 × 103 کيلوګرام / متر3, د جاذبې قوې له امله سرعت = ۵۰ متره/ثانیه2)
پیژندل شوی:
Height (h) = 165 cm = 165/100 m = 1.65 meters
Density of bloods (ρ) = 1.0 × 103 کيلوګرام / متر3
د جاذبې قوې له امله سرعت (g) = 10 m/s2
SE busca: liquid pressure
حل:
P = ρ g h
P = (1.0 × 103)(10)(1.65)
P = (1.0 × 104)(۵)
P = 1.65 x 104 N / م2
Pipe U
2. A U pipe is initially filled with water than on one pipe filled with oil, as shown in the figure below. The density of water is 1000 kg/m3. If the height of oil is 8 cm and the height of the water is 5 cm, what is the density of oil?
پیژندل شوی:
Density of water = 1000 kg.m-3
The height of water (h2) = ۴۰ سانتي متره
The height of oil (h1) = ۴۰ سانتي متره
غوښتل شوي: د تیلو کثافت
حل:
ρ1 غ1 =ρ2 غ2
ρ1 h1 =ρ2 h2
(1000)(5) = (ρ2)(۵)
5000 = (ρ2)(۵)
ρ2 = ۸۰۰ کیلو ګرامه متره-3
3. A U pipe was first filled with kerosene then added water. If the mass of kerosene is 0.8 grams/cm3 او د د اوبو کثافت is 1 gram/cm3 and the cross sectional area is 1.25 cm2. Determine how much water should be added so that the height difference of the kerosene surface is 15 cm
الف. ۵۰۰۰ ملی لیتره
B. 12 ml
C. 15 ml
D. 18 ml
پیژندل شوی:
Density of kerosene (ρ1) = 0.8 gram/cm3
Density of water (ρ2) = 1 gram/cm3
Sectional area of the pipe = 1.25،XNUMX سانتي متره2
The height difference of the surface of kerosene (h1) = ۴۰ سانتي متره
غوښتل شوي: د اوبو حجم
حل:
The height of water (h2):
ρ1 غ1 = ρ2 غ2
(0,8)(15)(1)(h2)
h2 = 12،XNUMX سانتي متره
Volume of water :
V = (Sectional area of the pipe)(height of water)
V = (1.25 cm2)(12 cm)
V = 15 cm3
1 liter = 1 dm3 = 103 cm3
1 mililiter = 10-3 لیټs = (10-3)(۵۰3) سانتي متره3 = 1،XNUMX سانتي متره3
Volume of water is 15 cm3 = 15 mililiters
سم ځواب C دی.
4. A pipe U filled with water with density of 1000 kg/m3. One column of pipe U filled with glyserin with density of 1200 kg/m3. If the height of glyserin is 4 cm, determine the height difference of both columns of the pipe.
الف. ۲۵۶۲.۵ سانتي متره
ب. ۲.۵ سانتي متره
ج. ۲۵۶۳ سانتي متره
د. ۳.۵ سانتي متره
پیژندل شوی:
Density of water (ρ1) = 1000 kg/m3
Density of glycerin (ρ2) = 1200 kg/m3
Height of glycerin (h2) = ۴۰ سانتي متره
SE busca: The height difference of both columns of the pipe.
حل:
The height of the column of the pipe (h1):
ρ1 h1 = ρ2 h2
(1000)(h1) = (۲۲۰)(۲)
(1000)(h1) = 4800،XNUMX
h1 = 4.8،XNUMX سانتي متره
The height difference of both columns of the pipe U = h1 - h2 = 4.8 cm – 4 cm = 0.8 cm
سم ځواب الف دی.
5. یو پایپ U has two ends are open filled with water سره a mass of 1 g / cm3. The sectional area along the pipe is the same, that is 1 cm2. Someone blows on one end of the foot of the pipe so that the surface of the water at the other foot rises 10 cm from its original position. If د سرعت due to gravity is 10 m/s2 then وټاکه ځواک acted by that شخص.
A. 20 kilodyne
B. 10 kilodyne
C. 2 kilodyne
D. 1 kilodyne
پیژندل شوی:
Change all units to the International system.
Density of water (ρ1) = 1 gr/cm3 = 10-3 kg / 10-6 m3 = 103 کيلوګرام / متر3
Cross sectional area of pipe (A) = 1 cm2 = 10-4 m2
The change of column of pipe (h) = 10 cm = 1 dm = 10-1 m
د جاذبې قوې له امله سرعت (g) = 10 ms ثانیې-2 = 101 اغلې-2
Volume of moved water (V) = (A)(h) = (1 cm2)(10 cm) = 10 cm3 = (101)(۵۰-6 m3) = 10،XNUMX-5 m3
غوښتل شوي: Force (F) acted by the person.
حل:
The force that acted by that person = weight of water with a height of 10 cm
ف = w
F = m g —–> Equation of density : م = ρ وی
F = ρ V g
ف = (۱۰)3)(۵۰-5)(۵۰1)
ف = (۱۰)4)(۵۰-5)
F=10-1 Newton —–> 1 Newton = 105 ډین
ف = (۱۰)-1)(۵۰5 dyne)
F=104 ډین
F = 10 kilodyne
سم ځواب ب دی.
6. A Y-shaped tube is inserted upside down so that the left foot and right foot are immersed in two kinds of liquid. After both feet are immersed in the liquid, then the top of the Y pipe is closed with the finger and pulled upwards, so that the two legs of the Y pipe are filled with a column of different high-density liquids. If the density of the first liquid is 0.80 gram.cm-3 and the second density is 0.75 gram.cm-3, and the lower liquid column is 8 cm, then وټاکه the height difference between the two liquid columns on U pipe.
الف. ۲۵۶۲.۵ سانتي متره
ب. ۲.۵ سانتي متره
ج. ۲۵۶۳ سانتي متره
د. ۳.۵ سانتي متره
پیژندل شوی:
Density of first liquid (ρ1) = 0,80 gram.cm-3
Density of second liquid (ρ2) = 0,75 gram.cm-3
The height of the lower liquid (h1) = ۴۰ سانتي متره
غوښتل شوي: The height difference between the two liquid columns on U pipe
حل:
The height of the higher liquids (h2):
ρ1 h1 = ρ2 h2
(0.80)(8) = (0.75)(h2)
6.4 = 0.75 (h2)
h2 = 6.4/0.75
h2 = 8.5،XNUMX سانتي متره
The height difference of liquids = h2 - h1 = 8.5333 cm – 8 cm = 0.5333 cm
سم ځواب D دی.
7. A stone with the volume of 0.5 m3 placed in a liquid with the density of 1.5 gr cm-3. Acceleration due to gravity is 10 m s-2. What is the buoyant force?
پیژندل شوی:
د ډبرې حجم (V) = 0.5 متر3
Density of water (ρ) = 1.5 gr cm-3 = 1500 کیلوګرامه متر-3
Acceleration due to gravity (g) = 10 m s-2
SE busca: buoyant force (FA)
حل:
The equation of the buoyant force :
FA = ρ g V = (1500 kg m-3)(10 m s-2)(0.5 متر3) = ۱۰ کیلوګرامه متر مکعب/ثانیه2 = ۱۰ نیوټن
فلټ
8. A block of ice float in the sea as shown in the figure below. The density of sea is 1.2 gr cm-3 and density of ice is 0.9 gr c-3. The volume of ice in sea water = ……. x the volume of ice in the air.
پیژندل شوی:
Density of sea (ρسمندر) = ۱.۲ ګرامه سانتي متره-3
Density of ice (ρیخ) = 0.9 ګرامه ج-3
SE busca: The volume of ice in sea water = ……. x the volume of ice in the air.
حل:
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The volume of ice in sea = 0.75
The volume of ice in air = 0.25
The volume of ice in sea water = 3 x the volume of ice in air (3 x 0.25 = 0.75).
9. An object float in a liquid where 2/3 of the object in the liquid. If the density of the object is 0.6 gr cm3, then what is the density of water.
پیژندل شوی:
The part of the object in liquid = 2/3
Density of object = 0.6 gr cm3 = 600 کیلوګرامه متر3
SE busca: the density of the liquid (x)
حل:

The density of the liquid is 900 kg m3
10. A wood float in water, where 3/5 part of wood in the water. If the density of water is 1 × 103 کيلوګرام / متر3, what is the density of wood?
پیژندل شوی:
Part of object in water = 3/5
Density of water = 1×103 کيلوګرام / متر3 = 1000 kg/m3
غوښتل شوي: The density of wood (x)
حل:

The density of wood is 600 kg/m3 = 6x102 کيلوګرام / متر3
- What is fluid statics?
- ځواب: Fluid statics, also known as hydrostatics, is the branch of fluid mechanics that studies fluids at rest and the forces exerted by static fluids on immersed objects and container walls.
- How does pressure in a fluid vary with depth?
- ځواب: In a static fluid, pressure increases linearly with depth due to the weight of the fluid column above any given depth. The change in pressure with depth is given by ، چې د is the fluid density, is the gravitational acceleration, and ℎ د is the depth.
- What is Pascal’s principle?
- ځواب: Pascal’s principle states that a change in pressure applied to an enclosed fluid is transmitted undiminished to all portions of the fluid and to the walls of its container.
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- ځواب: A hydraulic lift utilizes Pascal’s principle. When a small force is applied to a small piston, it creates a pressure in the fluid. This pressure is transmitted undiminished throughout the fluid, exerting a much larger force on a larger piston, enabling the lift to raise heavy objects with relatively little effort.
- What is buoyant force and how is it related to fluid statics?
- ځواب: The buoyant force is the upward force exerted by a fluid on any immersed object. According to Archimedes’ principle, the buoyant force on an object is equal to the weight of the fluid displaced by the object.
- Why do objects float or sink in fluids?
- ځواب: Whether an object floats or sinks depends on the relationship between the buoyant force and the object’s weight. If the buoyant force (due to the displaced fluid) is greater than the object’s weight, it will float. If the object’s weight is greater, it will sink.
- What is the concept of hydrostatic pressure?
- ځواب: Hydrostatic pressure is the pressure exerted by a fluid at rest due to the force of gravity. It increases linearly with depth in the fluid, and is calculated as ، چې د is the pressure at the surface, is the fluid density, is the gravitational acceleration, and ℎ د is the depth.
- How is atmospheric pressure related to fluid statics?
- ځواب: The atmosphere can be thought of as a fluid. Atmospheric pressure is the pressure exerted by the weight of the air above a given point. It decreases with altitude, similar to how pressure in a liquid decreases as one moves upward in the fluid column.
- What role does the shape of a container play in the pressure distribution of a static fluid within it?
- ځواب: In fluid statics, the pressure at a given depth depends only on the height of the fluid column above that depth, not on the shape of the container. Thus, pressure at a specific depth is the same regardless of the container’s shape.
- What is the significance of the hydrostatic paradox?
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