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Explain why (a). The blood pressure in...

Explain why
(a). The blood pressure in humans is greater at the feet than at the brain
(b). Atmospheric pressure at a height of about 6 km decreases to nearly half of its value at the sea level, through the height of the atmosphere is more than 100 km
(c). Hydrostatic pressure is a scalar quantity even though pressure is force divided by area.

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The pressure of a liquid is given by the relation:
`P = rhogh` Where,
`P = Pressure`
`h =` Height of the liquid column
`rho =` Density of the liquid
`g =` Acceleration due to the gravity
It can be inferred that pressure is directly proportional to height. Hence, the blood pressure in human vessels depends on the height of the blood column is the body. The height of the blood column is more at the feet than it is at the brain. Hence, the blood pressure at the feet is more than
(b) Density of air is the maximum near the sea level. Density of air decreases with increases in height from the surface. At a height of about `6 km`, density decreases to nealy half of its value at the sea level. Atmospheric pressure is proportional to density. Hence, at a height of `6 km` from the surface, it decreases to nearly half of its value at the sea level.
(c) When force is applied on a liquid, the pressure in the liquid is transmitted in all directions. Hence, hydrostatic pressure does not have a fixed direction and it is a scalar physical quantity.
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Explain why (a) the blood pressure is humans is greater at the feet than at the brain. (b) Atmospheric pressure at a height of about 6 km decreases to nearly half its value at the sea level through the 'height' of the atmospheric is more than 100 km. (c) Hydrostatic pressure is a scalar quantity even though pressure is force divided by area , and force is a vector.

Hydrostatic pressure is a scalar quantity, even though pressure is force divided by area and force is a vector? Why?

Fluids at rest exert a normal force to the walls of the container or to the sruface of the body immersed in the fluid. The pressure exerted by this force at a point inside the liqid is the sum of atmospheric pressure and a factor which depends on the density of the liquid, the acceleration due to gravity and the height of the liquid, above that point. The upthrust acting on a body immersed in a stationary liquid is the net force acting on the body in the upward direction. A number of phenomenon of liquids in motion can be explain by Bernoulli's theorem which relates the pressure, flow speed and height for flow of an ideal incompressible fluid. A container of large uniform corss sectional area. A resting on a horizontal surface holds two immiscible, non viscous and incompressile liquids of densities d and 2d , each of height H//2 as shown in the figure. The lower density liquid is open to the atmosphere having pressure P_(0) . Situation I: A homogeneous solid cylinder of length L(LltH//2) . cross sectional area A//5 is immersed such that it floats with its axis vertical at liquid -liquid interface with lenght L//4 in the denser liquid. The total pressure at the bottom of the container is

Fluids at rest exert a normal force to the walls of the container or to the sruface of the Body immersed in the fluid. The pressure exerted by this force at a point inside the liqid is the sum of atmospheric pressure and a factor which depends on the density of the liquid, the acceleration due to gravity and the height of the liquid, above that point. The upthrust acting on a body immersed in a stationary liquid is the net force acting on the body in the upward direction. A number of phenomenon of liquids in motion can be explain by Bernoulli's theorem which relates the pressure, flow speed and height for flow of an ideal incompressible fluid. A container of large uniform corss sectional area. A resting on a horizontal surface holds two immiscible, non viscous and incompressile liquids of densities d and 2d , each of height H//2 as shown in the figure. The lower density liquid is open to the atmosphere having pressure P_(0) . Situation I: A homogeneous solid cylinder of length L(LltH//2) . cross sectional area A//5 is immersed such that it floats with its axis vertical at liquid -liquid interface with lenght L//4 in the denser liquid. The density of the solid is

Suppose the density of air at Madras is rho_0 and atmosphere pressure is P_0. If we go up the density and the pressure both decreae. Suppose we wish to calculate the pressure at a height 10 km above Madras. Ilf we use the equation P_0-P=rho_0gz will we get a pressure more than the actual or less than the actual? Neglect the variation in g. Does your answr change if you also consider the variation in g?

The human ciculatory system can be thought of as a closed system of interconnecting pipes through which fluid is continuously circulated by two pumps the two pumps the right and left verticles of the heart, work as simple two-stroke force pumps. The muscles of the heart regulate the force by contracting and relaxing. the contraction (systole) lasts about 0.2s and a complete systole/diastole (contraction/relaxation) cycle lasts about 0.8s. For flood pressures and speeds in the normal range. the volume flow rate of blood through a blood vessel is directly proportional tot he pressure difference over a length of the vessel and to the fourth power of the radius of the vessel. The total mechanical energy per unit volume of blood just as it leaves the heart is E//V=rhogh+P+rhov^(2) Q. Why is diastolic blood pressure muchh lower than systolic pressure? A. because the heart exerts more force on the blood during diastole B. Because the heart exerts no force on the blood during diastole C. Because the radii of the blood vessels increase during diastole while the force exerted by the heart on the blood remains the same. D. Because the radii of the blood vessels increase during diastole while the force exerted by the heart on the blood remains the same.

Torricelli was the first do devise an experiment for measuring atmospheric pressure . He took calibrated hard glass tube , 1 m in lengt and of uniform cross section , closed at one end . He filled the whole tube with dry mercury taking care than no air or water droplets remain inside the tube , closed the opposite end of the tube tightly with thumb and inverted it . He put this inverted mercury tube into a mercury through , taking care that the end of the tube remains inside the mercury through , An interesting thing was noticed . Mercury in the tube fell down at first and then stopped at a particular position . The height was 76 cm above the free surface of mercury in the through . When the given tube was inclined or lowered in the mercury trough , the vertical haight of mercury level in the tube was always found constant . Torricelli explained this by saying that the free surface of mercury in the trough . Hence , the hydrostatic pressure exerted by the trough measures the atmospheric pressure . If an additional hole is also made at P ' at the top point of the tube , then A. mercury will not come out of the tube B. mercury may come out of the tube after some time . C. mercury will come out of the tube instantly D. none of these

2.00 mole of a monatomic ideal gas (U=1.5nRT) is enclosed in an adiabatic, fixed , vertical cylinder fitted with a smooth, light adiabatic piston. The piston is connected to a vertical spring of spring constant 200 N m^(-1) as shown in .the area of cross section of the cylinder is 20.0 cm^(2) . initially, the spring is at its natural length and the temperature of the gas is 300K at its natural length. the atmosphere pressure is 100 kPa. the gas is heated slowly for some time by means of an electric heater so as to move the position up through 10 cm. find (a) the work done by the gas (b) the final temperature of the gas and (c ) the heat supplied by the heater.

At a depth of 1000 m in an ocean (a) what is the absolute pressure? (b) what is the gauge pressure? (c ) Find the force acting on the window of area 20 cm xx 20cm of a submarine at this depth, the interior of which is maintained at sea-level atmospheric pressure. The density of sea water is 1.03 xx 10^(3) kg m^(-3) , g=10ms^(-2) . Atmospheric pressure = 1.01 xx 10^(5) Pa .

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