Proteinuria, excess protein in the urine, is a symptom of many kidney diseases. A marker for proteinuria is a decrease in the surface tension of a urine sample over the course of a few hours, typically from 31 mN /m to 29 mN /m; the surface tension of normal urine does not change with time. The change in sur- face tension can be measured by monitoring the height of the liquid in a capillary tube. For a patient who has proteinuria, how high in mm will the liquid initially rise in a 0.80-mm- diameter capillary tube? How far will it fall over the course of a few hours? You can assume that the density of urine is the same as that

The blood pressure of an artery is measured at two heights: at the heart and 10 cm above the heart. The mass density of blood is about 1000 kg/m^3 and a typical artery has a diameter of 4 mm. (Use g = 10 m/s^2.) Compared to the pressure at heart height, the pressure 10 cm above is: Group of answer choices 100 P higher 1000 P lower 10 P higher 1000 P higher 100 P lower

Atherosclerosis is a cardiovascular disease that involves the accumulation of cholesterol in the arterial wall in regions with damaged endothelial cells. Assume that the damaged region is a circular hole with radius b. the thickness of the endothelial layer can be neglected. The endothelial layer is impermeable to cholesterol and plasma, except in the damaged region. The subendothelial space can be treated as a semi-infinite porous material with hydraulic conductivity K. The transport of fluid and cholesterol is in the radial direction and is symmetric about the center of the hole. The diffusion coefficient of cholesterol in the subendothelial tissue is D. The concentration of cholesterol and the hydrostatic pressure at r = b are approximately equal to those in the plasma, which are Cp and p0 respectively. The concentration and pressure at r→∞ are assumed to be zero. Determine the distribution of pressure in the subendothelial space in the steady state and evaluate the pressure at r =…

Air is evacuated from a vacuum chamber and the flow rate is measured. A section of circular plumbing is removed and replaced with a piece having a radius that is half the size of the original. The flow rate is measured again. What is the ratio of the new flow rate to the old flow rate?

The average body density of a human is 1030 kg/m3, yet we typically float in seawater when we fill our lungs with air and sink when we exhale. Therefore, our effective density is similar to that of seawater, 1010 kg/m3. If the typical total volume (body density + lung capacity) of a human is 0.25 m3, what volume is due to body mass and what volume is due to lung capacity (you can assume the density of air is rair = 1.2 kg/m3)

A 7.20 kg rock whose density is 4900 kg/m3 is suspended by a string such that half of the rock's volume is underwater. What is the tension in the string?

A cylindrical blood vessel is partially blocked by the buildup of plaque. At one point, the plaque decreases the diameter of the vessel by 70.0%. The blood approaching the blocked portion has speed ?0. Just as the blood enters the blocked portion of the vessel, what is its speed ?, expressed as a multiple of ?0? ?=   × ?0

the plunger and the needle of a hypodermic syringe have areas of 0.5 cm^2 and 0.0006 cm^2, respectively. To inject a vaccine, a nurse pushes the plunger with a force of 5.5 N. What pressure is transmitted into the vaccine?

The density of ice is 917 kg/m3, and the density of sea water is 1025 kg/m3. A swimming polar bear climbs onto a piece of floating ice that has a volume of 6.29 m3. (a) What is the weight of the heaviest bear that the ice can support without sinking completely beneath the water? To verify her suspicion that a rock specimen is hollow, a geologist weighs the specimen in air and in water. She finds that the specimen weighs twice as much in air as it does in water. The density of the solid part of the specimen is 5.42 × 103 kg/m3. (b) What fraction of the specimen’s apparent volume is solid?

A wooden raft has a mass of 50 kg. When empty it floats in water (density 1000 kg/m3) with 69% of its volume submerged. What mass of sand can be put on the raft without it sinking?