287 CHAPTER 6 form flow at locations 1 and 2. Develop a relationship for the force Fp acting on the sluice gate as a function of depths y, and vas mass flow rate m, gravitational constant g, gate width w, and water density p. Sluice gate y1 V1 V2 y2 FIGURE P6-46 6-46 A sluice gate, which controls flow rate in a channel by simply raising or lowering a vertical plate, is commonly used in irrigation systems. A force is exerted on the gate due to the difference between the water heights y, and y2 and the flow velocities V, and V2 upstream and downstream from the gate, respecti vely. Take the width of the sluice gate (into the page) to be w. Wall shear stresses along the channel walls may be ignored, and for simplicity, we assume steady, uni-

287 CHAPTER 6 form flow at locations 1 and 2. Develop a relationship for the force Fp acting on the sluice gate as a function of depths y, and vas mass flow rate m, gravitational constant g, gate width w, and water density p. Sluice gate y1 V1 V2 y2 FIGURE P6-46 6-46 A sluice gate, which controls flow rate in a channel by simply raising or lowering a vertical plate, is commonly used in irrigation systems. A force is exerted on the gate due to the difference between the water heights y, and y2 and the flow velocities V, and V2 upstream and downstream from the gate, respecti vely. Take the width of the sluice gate (into the page) to be w. Wall shear stresses along the channel walls may be ignored, and for simplicity, we assume steady, uni-

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter14: Fluid Mechanics

Section: Chapter Questions

Problem 129CP: Fluid originally flows through a tube at a rate of 100 cm3/s. To illustrate the sensitivity of flow...

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Similar questions

Explain why the fluid reaches equal levels on either side of a manometer if both sides are open to the atmosphere, even if the tubes are of different diameters.
(a) Verify that a 19.0% decrease in laminar flow through a tube is caused by a 5.00% decrease in radius, assuming that all other factors remain constant. (b) What increase in flow is obtained from a 5.00% increase in radius, again assuming all other factors remain constant?
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(a) Verify that a 19.0% decrease in laminar flow through a tube is caused by a 5.00% decrease in radius, assuming that all other factors remain constant, as stated in the text. (b) What increase in flow is obtained from a 5.00% increase in radius, again assuming all other factors remain constant?
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Suppose you have a wind speed gauge like the pitot tube shown in Figure 14.32. By what factor must wad speed increase to double the value of h in the manometer? Is independent of be moving fluid and be fluid the Figure 14.32 Measurement of fluid speed on Bernoulli’s principle. (a) A manometer is connected to two tubes close together and small enough not to disturb the flow. Tube 1 is open at the end facing the flow. A dead spot having zero speed is created there. Tube 2 has an opening on the side, so the fluid has a speed v across; thus, pressure there drops. The difference in pressure at the manometer is 12v22 , so h is proportional to . 12v22 (b) This type of velocity measuring device is a Prandtl tube, also known as a pitot tube.
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Explain why the fluid reaches equal levels on either side of a manometer if both sides are open to the atmosphere, even if the tubes are of different diameters.
Fluid originally flows through a tube at a rate of 100 cm3/s. To illustrate the sensitivity of flow rate to various factors, calculate be new flow rate for following changes with all other factors remaining the same as in original conditions. (a) Pressure difference increases by a factor of 1.50. (b) A new fluid wit 3.00 times greater viscosity is substituted. (c) The tube is replaced by one having 4.00 times the length. (d) Another tube used with a 0.100 times the original. (e) Yet another tube is substituted with a radius 0.100 times the original and half length, and pressure difference is increased by factor of 1.50.