Oil having a density of 930 kg/m^{3} floats on water. A rectangular block of wood 4.00 cm high and with a density of 960 kg/m^{3} floats partly in the oil and partly in the water. The oil completely covers the block. How far below the interface between the two liquids is the bottom of the block?

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The approximate diameter of the aorta is 0.50 cm; that of a capillary is 10 μm. The approximate average blood flow speed is 1.0 m/s in the aorta and 1.0 cm/s in the capillaries. If all the blood in the aorta eventually flows through the capillaries, estimate the number of capillaries in the circulatory system.

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Water is forced out of a fire extinguisher by air pressure, as shown in the figure below. What gauge air pressure in the tank (above atmospheric pressure) is required for the water to have a jet speed of 30.0 m/s when the water level in the tank is 0.500 m below the nozzle?

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A certain fluid has a density of 1 080 kg/m^{3} and is observed to rise to a height of 2.1 cm in a 1.0-mm-diameter tube. The contact angle between the wall and the fluid is zero. Calculate the surface tension of the fluid.

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The inside diameters of the larger portions of the horizontal pipe depicted in the figure are 2.50 cm. Water flows to the right at a rate of 1.80 x 10^{-4} m^{3}/s. Determine the inside diameter of the constriction.

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A large storage tank, open to the atmosphere at the top and filled with water, develops a small hole in its side at a point 16.0 m below the water level. If the rate of flow from the leak is 2.50 x 10^{-3} m^{3}/min, determine (a) the speed at which the water leaves the hole and (b) the diameter of the hole.

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a) Calculate the mass flow rate (in grams per second) of blood (ρ = 1.0 g/cm ^{3}) in an aorta with a cross-sectional area of 2.0 cm^{2} if the flow speed is 40 cm/s.

b) Assume that the aorta branches to form a large number of capillaries with a combined cross-sectional area of 3.0 x 10^{3} cm^{2}. What is the flow speed in the capillaries?

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A 1.00-kg beaker containing 2.00 kg of oil (density = 916 kg/m ^{3}) rests on a scale. A 2.00-kg block of iron is suspended from a spring scale and is completely submerged in the oil (Fig. P9.43). Find the equilibrium readings of both scales.

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A table-tennis ball has a diameter of 3.80 cm and average density of 0.0840 g/cm ^{3}. What force is required to hold it completely submerged under water?

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A container is filled to a depth of 20.0 cm with water. On top of the water floats a 30.0-cm-thick layer of oil with specific gravity 0.700. What is the absolute pressure at the bottom of the container?

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The four tires of an automobile are inflated to a gauge pressure of 2.0 x 10 ^{5} Pa. Each tire has an area of 0.024 m^{2} in contact with the ground. Determine the weight of the automobile.

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The tires on a new compact car have a diameter of 2.0 ft and are warranted for 60,000 miles. (a) Determine the angle (in radians) through which one of these tires will rotate during the warranty period. (b) How many revolutions of the tire are equivalent to your answer in part (a)?

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A wheel has a radius of 4.1 m. How far (path length) does a point on the circumference travel if the wheel is rotated through angles of (a) 30°, (b) 30 rad, and (c) 30 rev, respectively?

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