Physics - Fluids. Read Page 174 (Density) TQ1. A fluid is what type of matter? TQ2. What is fluid mechanics? TQ3. What is the equation for density?

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1 Homework Procedure: Read pages specified in Honors Physics Essentials by Dan Fullerton. Questions labeled TQ will be questions about the text you read. These TQ s can be answered in one word, one phrase, or a complete sentence. Questions labeled CQ are conceptual questions and must be answered in complete sentences. Questions labeled QQ s are quantitative questions and the equation, substitution with units, and solve with units must be shown on your paper. CQ s and QQ s will be similar to the questions found in the Honors Physics Essentials textbook. Read Page 174 (Density) TQ1. A fluid is what type of matter? TQ2. What is fluid mechanics? TQ3. What is the equation for density? TQ4. What is the symbol and units of density? QQ5. A perfect cube of aluminum has a mass of 21.2 kg and a length of 0.2 m. What is the density of aluminum? QQ6. Lead has a density of kg/m 3. How much volume does a 2 kg sample of lead occupy? CQ7. Salt water has a density of 1025 kg/m 3. Will a cube of ice (ρ = 917 kg/m 3 ) float or sink in salt water?

2 Read Page 175 (Buoyancy) TQ8. What is buoyancy? TQ9. What did Archimedes notice when he submerged himself in his tub? TQ10. As Archimedes ran down the street naked and wet, what did he yell? TQ11. What is the equation for Archimedes Principle? QQ12. What is the buoyant force on a 0.5 m 3 lead cube that is fully submerged in freshwater (ρ = 1000 kg/m 3 )? QQ13. A string holds a 5 kg metal object fully submerged in saltwater (ρ = 1025 kg/m 3 ). What is the force of gravity on the 5 kg metal object? QQ14. In question QQ13 what is the force of buoyancy on the metal object if it displaces m 3 of saltwater when fully submerged? QQ15. What is the force of tension in the string due to questions QQ13 and QQ14? QQ16. A boat has a mass of 2000 kg and it floats on a freshwater lake (ρ = 1000 kg/m 3 ). What volume of the boat is submerged in the lake?

3 Read Page 178 (Pressure) TQ17. What is the physics equation for pressure? TQ18. What is the SI unit of pressure? TQ19. Why can a man lay down on a bed of nails not get hurt? TQ20. What is the pressure due to the atmosphere? QQ21. What force is exerted on an object with an area of m 2 by the atmosphere (atmospheric pressure = 1 x 10 5 Pa)? QQ22. A physics textbook has a mass of 2.0 kg. It has an area of 0.06 m 2. What is the pressure exerted by the physics textbook on a table? QQ23. Mars has an atmospheric pressure of 700 Pa. If the mars rover has a weight of 1972 N on Mars surface, what is the surface area of the rover? QQ24. What is the pressure that the ground experiences by a 1400 kg automobile with a 0.25 m 2 total tire contact area? TQ25. What is the equation for the gauge pressure of a submerged object? TQ26. If the density of a fluid stays the same, what is the only variable that affects gauge pressure? TQ27. In order to find absolute pressure, what do you add to the gauge pressure? QQ28. If you are fully submerged at a depth of 2 m in a freshwater lake ((ρ = 1000 kg/m 3 ), what is your gauge pressure? QQ29. What is the absolute pressure in QQ29? QQ30. The gauge pressure of an object in saltwater ((ρ = 1025 kg/m 3 ) is Pa. How deep is the object?

4 Read Page 181 (Pascal s Principle) TQ31. If Pascal s Principle states that P 1 = P 2, what does F 1 A 1 =? QQ32. If a 200 N force is applied over an area of m 2 of a hydraulic piston, what force can it lift with an area of 0.1 m 2? QQ33. An auto mechanic is raising a N car on a hydraulic lift with an area of 0.70 m 2. What force must be exerted on the piston area of m 2 in order to lift the car?

5 Read Page 183 (Continuity Equation for Fluids) Physics - Fluids TQ34. How does the law of conservation of mass apply to fluids? TQ35. What is the fluid continuity equation? TQ36. What happens to the velocity of a fluid if the pipe area gets smaller? QQ37. Water is flowing at 0.08 m/s through a hose with a cross-sectional area of 0.5 m 2. If the same water then runs through a nozzle with a cross-sectional area of m 2, what speed is the water flowing at out of the nozzle? QQ38. Water flows through from a small tube radius to a large tube radius. The small tube radius is m and the large tube radius is m. Calculate the cross-sectional areas of the small tube and the large tube. QQ39. If the water is flowing at 5 m/s in the small tube in QQ38, what speed is the water flowing in the large tube?

6 Read Page 185 (Bernoulli s Principle) TQ40. Bernoulli s Principle states that fluids moving at higher speeds lead to what kind of pressure? TQ41. What is the full equation for Bernoulli s Princple? TQ42. What does the equation ½ ρv 2 remind you of? TQ43. What does the equation ρgy or ρgh remind you of? CQ44. Which value in the picture above makes the water flow with a velocity out of the hole h or d? CQ45. A container filled with freshwater (ρ = 1000 kg/m 3 ) is filled to the top of a large tank that is 25 m above the ground. There is a plug 5 m above the ground that breaks and water begins to flow out of the hole. What velocity will the water leave the hole?

7 Free Response A steel plate (density of 7800 kg/m 3 ) is lowered using a cable down to a depth of 50 m under the ocean s surface. The plate has dimensions of a surface area of 0.70 m 2 and a height of 0.10 m. The density of ocean water is 1025 kg/m 3. (A) Calculate the gauge pressure on this steel plate. (B) Calculate the absolute pressure on this steel plate. (C) Calculate the force of the water on the surface of this steel plate. (Identify which pressure to use) (D) Calculate the volume of the steel plate in m 3. (E) Calculate the force due to buoyancy of ocean water on this steel plate. (F) Calculate the mass of the steel plate. (G) Calculate the force of gravity of the steel plate. (H) Calculate the force of tension on the cable..