Lista de Exercício - 2_Mecânica dos Fluidos

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<p>Lista de Exercício – 2</p><p>Mecânica dos Fluidos</p><p>1) The U-tube shown in Fig. is 10 mm in diameter and contains mercury. If 12 ml of water is poured</p><p>into the right-hand leg, what are the ultimate heights in the two legs?</p><p>2) Assuming sea water to have a constant specific weight of ⁄ , what is the absolute</p><p>pressure at a depth of ?</p><p>3) In Fig., Fluid 2 is carbon tetrachloride and fluid 1 is benzene. If is , determine the</p><p>absolute pressure at point .</p><p>4) A manometer is attached to a conduit, as shown in Fig. Calculate the pressure at point A.</p><p>a)</p><p>b)</p><p>c)</p><p>5) A differential manometer is shown in Fig. Calculate the pressure difference between points and</p><p>.</p><p>6) A differential manometer is attached to a pipe, as shown in Fig. Calculate the pressure difference</p><p>between points and .</p><p>a)</p><p>b)</p><p>7) Water flows downward in a pipe at , as shown in Fig. the pressure drop is partly due</p><p>to gravity and partly due to friction. The mercury manometer reads a 12.7 cm height difference.</p><p>What is the total pressure drop ? What is the pressure drop due to friction only between</p><p>1 and 2? Does the manometer reading correspond only to friction drop?</p><p>8) A dam 20 m long retains 7 m of water, as shown in Fig. Find the total resultant force acting on the</p><p>dam and the location of the center of pressure.</p><p>9) A tank of dye has a right-triangular panel near the bottom as shown in Fig. Calculate the resultant</p><p>force on the panel and locate its center of pressure.</p><p>10) Calculate the resultant force on triangular window ABC in Fig. and locate its center of pressure.</p><p>11) The gate in Fig. is wide, is hinged at point , and rests against a smooth wall at A.</p><p>Compute (a) the force on the gate due to seawater pressure, (b) the horizontal force exerted by</p><p>the wall at point A, and (c) the reaction at hinge .</p><p>12) Gate in Fig. is semicircular, hinged at . What horizontal force is required at for</p><p>equilibrium?</p><p>13) The submerged, curved surface AB in Fig. is one-quarter of a circle of radius . The</p><p>tank’s length is . Find the horizontal and vertical components of the total resultant</p><p>force acting on the curved surface and their locations.</p><p>14) Solve Prop.14 for the same given conditions except that water is on the other side of curved</p><p>surface , as shown in Fig.</p><p>15) The canal shown in cross section in Fig. runs into the paper. Determine the horizontal and</p><p>vertical components of the hydrostatic force against the quarter-circle wall and the point c.p.</p><p>where the resultants strikes the wall.</p><p>16) Determine the magnitude and direction of the force necessary to hold a concrete cube, on</p><p>each side, in equilibrium and completely submerged (a) in mercury(Hg) and (b) in water. Use</p><p>.</p><p>17) A barge is loaded with of coal. The weight of the empty barge in air is . If the</p><p>barge is wide, long, and high, what is its draft(i.e., its depth below the water</p><p>surface)?</p><p>18) Find the specific weight of the sphere shown if its volume is . State all assumptions.</p><p>What is the equilibrium position of the sphere if the weight is removed?</p><p>19) Hydrogen bubbles are used to visualize water flow streaklines in the video, Flow Visualization. A</p><p>typical hydrogen bubble diameter is d=0.0254 mm. The bubbles tend to rise slowly in water</p><p>because of buoyancy; eventually they reach terminal speed relative to the water. The water force</p><p>of the water on a bubble is given by , where is the viscosity of water and is the</p><p>bubble speed relative to the water. Find the buoyancy force that acts on a hydrogen bubble</p><p>immersed in water. Estimate the terminal speed of a bubble rising in water.</p><p>20) In a logging operation, timber floats downstream to a lumber mill. It is a dry year, and the river is</p><p>running low, as low as 60 cm in some locations. What is the largest diameter log that may be</p><p>transported in this fashion(leaving a minimum 5 cm clearance between the log and the bottom of</p><p>the river)? For the wood, SG=0.8.</p>