Physics-Fluids Uworld

What is the equation of Hydrostatic Pressure?

Ph=p(rho)gh

1 atm= What in mmHg and Pa?

1 atm=760mm Hg=100,000 Pa

What does the Simple Fluid Barometer measure?

1. A device used to measure Patm (atmospheric Pressure)

What is the equation that shows the Blood Pressure drop in arterioles with one capillary network?

1. Blood Pressure drop in Arterioles: 2. Delta P=PB - PE 3. Delta P= Blood Pressure Drop 4. PB= Beginning of Pressure of Vessel 5. PE= Ending pressure of the Vessel

A 30-year-old woman has an average bone tissue density of 1.8 g/cm3 with an estimated bone tissue volume of 5,000 cm3. Assuming her bone tissue volume remains the same, what will her bone tissue density be if she is expected to lose 1.5 kg of bone mass by age 70 due to osteoporosis? A.0.7 g/cm3 B.1.2 g/cm3 C.1.5 g/cm3 D.2.1 g/cm3

1. Given: m30: 1.8 g/cm^3 volume: 5,000 cm^3 m70: Lost 1.5 kg of bone 1. Solve for Mass (m) at 30 years old: m=ρV M30=(1.8gcm3)(5,000 cm3)=9,000 g 2. Convert 1.5 to kg 1.5kg=1,500g 3. Subtract this mass with m30: m70=9,000 g−1,500 g=7,500 g 4. Now calculate Density at 70: ρ70=m70V=7,500 g5,000 cm3=1.5gcm3

What are the two factors that affect Buoyant Force?

1. How much water is displaced (volume of water pushed out) 2. The density of the object Ex: A stone is super dense, and no water is displaced; therefore, it sinks Ex: A football is NOT that dense, and there is and displaces much water therefore, it floats

What are the three characteristics of Fluids?

1. No viscosity: a. No friction bw fluid molecules 2. Laminar Flow: a. Smooth flow in layers, fluid travel in straight lines 3. Incompressible: a. Unform density

What is Atmospheric pressure?

1. Pressure that gas molecules in the atmosphere exert on ALL terrestrial objects (bodies of water, living beings)

What does the hydrostatic pressure in a Barometer equal to?

1. Product of the Fluid Density 2. Gravitational acceleration 3. Height of the Mercury in the Tube

What is hydrostatic pressure?

The pressure that the fluid exerts on the walls of its container

What is Hydrostatic Pressure?

The pressure exerted by the weight of the fluid above a point

What does Bernoulli's principle state?

The pressure of a fluid decreases when the speed of the fluid increases So: As v increases, p decreases. vag> peni

What does the Volumetric Flow Rate describe?

The volume of a fluid that is passing through a given cross sectional area Its what keep you alive! Your heart pumps a volume of blood roughly equal to the volume of a can of soda every four seconds

Ideal fluids are used to model the behavior of fluids both in motion and at rest. Which one of the following assumptions does NOT apply to an ideal fluid? A.The direction of the flow is equal at all points within a moving fluid. B. Fluid pressure is not influenced by fluid velocity. C.Frictional forces between fluid molecules are negligible. D. The fluid is incompressible.

B. Fluid pressure is NOT influenced by fluid velocity Fluid and pressure are inversely proportional As V goes up, P goes down

What does the pulse wave velocity equal to?

Frequency and the wavelength

What is the equation for Volumetric flow rate?

Q= Of blood flowing through a vessel A= Area of the blood vessels V= Velocity of Blood A= πr2 Q=Av Q=πr2

What is the equation for Snells Law?

n1sinθ1=n2sinθ2 n1: Refractive index of glass θ1= Incidence Angle n2= Refractive Index of Lens θ2= Transmitted Angle

A cube with a side length of 5 cm floats on the surface of water. If 4/5 of the cube volume floats above the surface of the water, what is the density of the cube? (Note: Density of water = 1,000 kg/m3.) Draw a cube floating on water

1. Use the Archimedes Principle Equation: pobject/pfluid= Vfluid/Vobject= Given: The question states that "4/5" of the (Vobject) floats ABOVE the surface of the water So.. 1/5 of the (Vobject) is BELOW the water surface Cube shows a displacement volume of water that is 1/5 its own volume 1/5= Vfluid/Vobject= Pobject/Pfluid Pfluid= (density of water)=1,000 kg/m^3 Pobject= (1/5)(1,000kg/m^3)=200kg/m^3

What is a real life example of the Archimedes principle?

1. When you get into the bathtub (weight) the water raises as soon as you get in and some water might come out 2. A ship floating on water

What is the equation for the relationship between the density and volume of a floating object? (Archimedes Principle)

1. pobject/pfluid= Vfluid/Vobject= a. pobject: Object density b. pfluid: Fluid Density c. Vfluid: Displacement volume d. Vobject: Object volume

What is the equation for density?

1. ρ=mV D=mass volume

What does Archimedes principal state?

Buoyant Force of a floating object=Weight of the fluid displaced by the floating object

What is the Buoyant force mean?

Buoyant force states weather not something sinks or floats

Atmospheric pressure on a distant planet causes water to rise to a height of 10 m inside an evacuated tube with its open end immersed in a container of water open to ambient pressure. What is the atm pressure? Note: Density= 10^3 kg/m^3 Gravitational Force=20m/s^2 Picture: The tube and its open end are immersed in a container of water to open the water. Have to over math!

Given: 1. h=10m 2. p(row): 10^3 kg/m^3 3. Gravitational Force= 20 m/s^2 Find: Atm pressure: Steps: 1. Use the equation: Patm=Ph=pf(row)g h Patm= (10^3 kg/m^3)(20m/s^2)(10m)= Patm=2x10^5 kg m^2/m^3s^2= 2x10^5 kg m/m^2 s^2 P atm: 2x10 N (1/m^2)= 2x10^5Pa

What occurs in Snell's Law?

It is the relationship between the angle of incidence and refractive angles

What is the equation for hydrostatic pressure? P=ρgh

P=ρgh P=Pressure p=Density g-gravitational acceleration h=height

What is the equation for the simple fluid barometer?

Patm=Ph=pf(row)gh patm: Atomoshperic pressure Ph: Hydrostatic Pressure P(row)f: Fluid Density

The refractive indices of the glass optical fiber, polymer lens, and liquid crystal lens described in the passage are denoted as n1, n2, and n3, respectively. The refractive indices of the glass optical fiber and the two focusing lenses are related by which of the following? Passage: The incident angle of the laser in the glass fiber was held constant at 45°. The refracted angles for a polymer lens and a liquid crystal lens were 55° and 35°, respectively. A.n1 < n2 and n1 < n3 B.n1 > n2 and n1 > n3 C.n1 < n2 and n1 > n3 D.n1 > n2 and n1 < n3

This question is asking about is the relationship between the refractive indices of the glass optical fiber: Given: θ1= 45 (Incidence Angle) θ2= (Transmitted Angle) 1. n1= n2 (sin 55)/ (sin 45) > 1 2. n1=n3 (sin 35/sin 45) <1 3. n1>n2 and n1 < n3

Researchers determined that the blood velocity in the afferent arterioles of their model was four times larger than physiological measurements. Which of the following changes to their model could correct this discrepancy? (Note: Assume ideal fluid flow.) A.Increase the radius of the afferent arterioles by 100% (36%) B.Increase the radius of the afferent arterioles by 75% (16%) C.Decrease the radius of the afferent arterioles by 75% (26%) D.Decrease the radius of the afferent arterioles by 100% (20%)

This question is asking to find the velocity for the correct amount in the arterioles: SA: No idea how to answer: 1. Use the Volumetric Flow Rate: Q=Av 2. Q=πr2v 3. Q is constant over all the vascular regions in the kidney vasculature model. The equation above can be rearranged to solve for v: v=Qπr2 4. When r increases by 100% (ie, is doubled), the new value of v, denoted v1, equals: v1=Q/ π(2r)2=Q/ 4πr2 v1=0.25Q/πr2=0.25v increasing r by 100% causes v to decrease by 75% (ie, decrease to one fourth its original value), i

If the maximum pressure in a blood vessel is 7,000 Pa, what is the pressure in mmHg? (Note: The density of mercury is 14,000 kg/m3, and gravitational acceleration is 10 m/s2.) A.0.05 mmHg B.2 mmHg C.20 mmHg D.50 mmHg

This question is asking us to find the pressure of a blood vessel in mmHg? Converting Blood Pressure to mmHg in a barometer: Given: Max Pressure: 7,000 Pa p=Density= 10 m/s^2 p of Mercury= 14,000 kg/m^3 g=10m/s^2 Find: What is the pressure in mmHg? patm=Atmospheric Pressure Ph= Fluid Density pf=Gravitational Acceleration g=gravity h=fluid height Patm = Ph = ρfgh The equation above can be solved for h, yielding: h=Phρfg Ph in the mercury barometer equals the maximum blood vessel pressure PB, which is given as 7,000 Pa. From the equation above, h in meters of mercury is given by: h=7,000Nm2/(14,000kgm3)(10ms2) h= 0.05m of Hg 1. Convert m to mm: 0.05m x (1,000mmHg)/(1 m of Hg)= 50mmHg

Which of the following is closest to the expected drop in pressure in the arterioles for an organ with only one capillary network? A.100 mmHg B.70 mmHg C.40 mmHg D.20 mmHg

This question is asking what is closest to the expected drop in pressure in the arterioles for an organ with only 1 capillary network? You have to look at the graph and see where there is a Blood Pressure Drop in Arterioles? Delta P=PB - PE The 1st Blood Pressure Drop is at 90 mmHg and the 2nd Blood Pressure Drop was at 20 mmHg: What is the difference between the two? 90 mmHg - 20 mmHg= 70 mmHg

A clinical study reports that the time required for the pulse wave to arrive at the kidney increases after renal artery ablation. A possible explanation for this could be that: A.decreasing blood pressure causes the wavelength of the pulse wave to decrease. B.decreasing blood pressure causes the wavelength of the pulse wave to increase. C.decreasing blood pressure causes the frequency of the pulse wave to decrease. D.decreasing blood pressure causes the frequency of the pulse wave to increase.

This question is asking what is the reason that a pulse wave arrives at the kidney increases the renal ablation is due to? SA: ? When the frequency is constant, changes in the pulse wave velocity cause a proportional change in the wavelength. A.decreasing blood pressure causes the wavelength of the pulse wave to decrease.