Handout2 fluida statik

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    19-Jul-2015

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<ul><li><p>SasaranFLUIDA STATIKHYDROSTATICS PRINCIPLES</p><p>Dapat menghitung distribusi tekanan dan gaya pada benda yang terendam dalam fluida.</p><p>Dapat menghitung cara menghitung tekanan menggunakan differential manometry.</p><p>Dapat a menggunakan manometer untuk mengukur tekanan</p></li><li><p>Review FLUIDA STATIKTEKANAN P = F/A</p><p>EFEK GRAVITASI PADA TEKANANP = P0 + rgd</p><p>GAYA BUOYANT F = r g V</p><p>05</p></li><li><p>TEKANANGaya per satuan luas, dimana gaya tegak lurus luasan. Tekanan absolut adalah tekanan relatif terhadap vakumTekanan gauge, yaitu tekanan relatif terhadap atmosfir ( p-pa)patmosfir= 1.013X105 Nm-2Pa (Pascal)1 psi = 6895 Pa</p></li><li><p>Seseorang menginjak jari kakimu dengan gaya 500 N pada luasan 1.0 cm2. Berapa atmosfir tekanan tersebut .TEKANAN</p></li><li><p>TEKANAN DALAM BEJANATekanan timbul karena adanya tabrakan antara partikel fluida dengan dinding bejana (molecules bouncing )Ada perubahan momentum (impulse), jika partikel menabrak dinding, balik arah menjauhi dinding wadah. Jadi pasti ada gaya bekerja pada partikel dan dinding,</p></li><li><p>Pascals PrinciplePerubahan tekanan pada semua titik dalam fluida diteruskan keseluruhan fluida. </p></li><li><p>Gaya force F1 bekerja pada piston A1.Gaya ditransmisikan ke piston A2.F2Assume F1 = 500 NA1A2</p><p>F21500 N105000 N10050,000 N</p></li><li><p>EFEK GRAVITASI PADA TEKANAN FLUIDAF = gaya dari atas + gaya dari bawah + gaya gravitasi = 0Tekanan atasPb Tekanan bawah PaZaZbDensitas=Dz</p></li><li><p>EFEK GRAVITASI PADA TEKANAN FLUIDAdPAtm</p></li><li><p>TEKANAN DENGAN KEDALAMANUntuk gas(gas ideal, isotermal)Untuk cair</p></li><li><p>Tekanan pada permukaan air danau adalah 105 kPa. Hitung tekanan pada kedalaman 35.0 m dibawah permukaan air.Kerapatan air segar</p></li><li><p>Tekanan di permukaan planet Venus adalah 95 atm. How far below the surface of the ocean on Earth do you need to be to experience the same pressure?Density of sea water</p></li><li><p>PENGUKURAN TEKANANA manometer is a U-shaped tube that is partially filled with liquid.Both ends of the tube are open to the atmosphere.</p></li><li><p>A container of gas is connected to one end of the U-tubeCBBAdPoint A is the original location of the top of the fluid before the gas cylinder is connected.</p></li><li><p>Using a u-tube manometer to measure gauge pressure of fluid density 700 kg/m3, and the manometric fluid is mercury, with a relative density of 13.6. What is the gauge pressure if: a). h1 = 0.4m and h2 = 0.9m? b) h1 stayed the same but h2 = -0.1m? </p><p>THE U-TUBE MANOMETER. </p></li><li><p>Measuring Pressure BarometersA barometer is used to measure the pressure of the atmosphere. The simplest type of barometer consists of a column of fluid.p1 = 0vacuumhp2 = pap2 - p1 = ghpa = ghexampleswater: h = pa/g =105/(103*9.8) ~10mmercury: h = pa/g =105/(13.4*103*9.8) ~800mm</p></li><li><p>Atmospheric pressure is equivalent to a column of mercury 76.0 cm tall.</p></li><li><p>ARCHIMEDES PRINCIPLE Buoyant Force (FB) weight of fluid displaced</p><p>FB = fluidVdisplaced g Fg = mg = object Vobject g object sinks if object &gt; fluid object floats if object &lt; fluid object floats if fluid = object</p></li><li><p>ARCHIMEDES EXAMPLEA cube of plastic 4.0 cm on a side with density = 0.8 g/cm3 is floating in the water. When a 9 gram coin is placed on the block, how much sinks below water surface?hkoin</p></li><li><p>ARCHIMEDES EXAMPLES F = m aFb Mg mg = 0r g Vdisp = (M+m) gVdisp = (M+m) / rh A = (M+m) / rh = (M + m)/ (r A) = (51.2+9)/(1 x 4 x 4) = 3.76 cmM = plastic Vcube = 0.8x4x4x4 = 51.2 ghkoin</p></li><li><p>Wadah segi 4 berdasar datar diisi dengan coal, massanya 3.0105 kg. Panjang 20 m dan lebar 10m, mengambang diair. Berapa kedalaman wadah masuk ke dalam air.</p></li><li><p>Go up, causing the water to spill out of the glass. Go down. Stay the same.COBA PIKIRKANB = W g VdisplacedW = ice g Vice W g VMust be same!ice-cubeSebuah balok es mengambang diatas segelas air, sampai permukaan air rata pada pinggiran. Ketika es meleleh maka air di dalam akan : </p></li><li><p>COBA PIKIRKANWhich weighs more: 1. A large bathtub filled to the brim with water. 2. A large bathtub filled to the brim with water with a battle-ship floating in it. 3. They will weigh the same.Weight of ship = Buoyant force =Weight of displaced water16</p></li><li><p>Sepotong logam dilepaskan dibawah air water. Volume metal 50.0 cm3 dan SG 5.0. Hitung percepatan initialnya, saat v=0 tidak ada gaya drag.</p></li><li><p>FB adalah berat fluida yang dipindahkan oleh bendawater = 1000 kg/m3 (at 4 C).</p></li><li><p>KEDALAMAN OIL RESERVOIR What the depth below the surface of oil reservoir that produce oil with relative density 0.8 and wellhead pressure of 120 kN/m2? water = 1000 kg/m3, and p atmosphere = 101kN/m2. </p></li><li><p>DECANTERS GRAVITY </p></li><li><p>DECANTERIt is proposed to use a gravity decanter to separate a light petroleum oil (density 50.0 lbm/ft3) from water (density 62.3 lbm/ft3). Its desire to maintain a total depth of 30 in. in the vessel and to have exactly equal depth of oil and water. What should be the height , expressed in inch of the water discharge leg above the bottom of the vessel.</p></li><li><p>TEKANAN DALAM BENDA YANG BERGERAKGerak lurus</p></li><li><p>ExampleAn open tank contains water 5m deep. It is sitting on an elevator. Calculate the gauge pressure at the bottom of the tank(a) when the elevator is standing still, (b) when the elevator is accelerating upward at the rate of 5m/s2, and (c) when the elevator is accelerating downward at the rate of 5 m/s2.</p></li><li><p>TEKANAN DALAM BENDA RIGID BERGERAKGerak rotasiCentripetal accelaration =(angular velocity)2.radius</p></li><li><p>DECANTERSCentrifugal</p><p>*Note previous comes from F=ma. New material comes from conservation of energy!*1*Transparency*Transparency</p></li></ul>