F7.10 The flame spread rate through porous solids increases with concurrent wind velocity. decreases with concurrent wind velocity. is independent of concurrent wind velocity. F7.11 Surface tension accelerates opposed-flow flame spread over liquid fuels. True False F7.12 Opposed-flow flame spread rates over a solid surface are typically much smaller than 1 mm/s. around 1mm/s. much greater than 1 mm/s. F7.13 Upward flame spread rate over a vertical surface is typically between 10 and 1000 mm/s. True False F7.14 The Steiner tunnel test described in ASTM standard E 84 is used to assess the fire performance of interior finish materials based on lateral flame spread over a vertical sample. True False F8.1 Describe the triad of fire growth. F8.2 Liquid pool fires reach steady burning conditions within seconds after ignition. True False F8.3 The heat of gasification of liquid fuels is typically less than 1 kJ/g. between 1 and 3 kJ/g. greater than 3 kJ/g. F8.4 The heat flux from the flame to the surface of real burning objects can usually be determined with sufficient accuracy so that reasonable burning rate predictions can be made. True False F8.5 The mass burning flux generally associated with extinction is 0.5 g/m2s. 5 g/m2s. 50 g/m2s. F8.6 The mass burning flux of a liquid pool fire is a function of only the pool diameter. only the fuel type. pool diameter and fuel type. F8.7 The energy release rate of real objects can be measured in an oxygen bomb calorimeter. an oxygen consumption calorimeter. a room/corner test. F8.8 The peak energy release rate of typical domestic upholstered furniture can be as high as 3000 kW. True False F8.9 Draw a typical curve of the mass burning flux of a char forming fuel as a function of time. F8.10 A fast fire as defined in NFPA 72B grows proportionally to t2 and reaches an energy release rate of 1 MW in 75 sec. 150 sec. 300 sec. F9.1 Air entrainment into turbulent pool fire flames is due to buoyancy. True False F9.2 The frequency of vortex shedding in turbulent pool fire flames increases with pool diameter. decreases with pool diameter. is independent of pool diameter. F9.3 The height of turbulent jet flames for a given fuel type and orifice size is independent of energy release rate. True False F9.4 The exit velocities of fuel vapors leaving a solid or liquid pool fire surface are responsible for entrainment of air in the plume. True False F9.5 The height of a turbulent pool fire flame is a function of only energy release rate. only pool diameter. energy release rate and pool diameter. F9.6 Turbulent pool fire flame heights fluctuate in time within a factor of 2. True False F9.7 The Q* value for jet fires is 102 or greater. 104 or greater. 106 or greater. F9.8 The temperature in the continuous flame region of moderate size turbulent pool fires is approximately 820°C. True False F9.9 The temperature at the maximum flame height of a turbulent pool fire flame is approximately 1200°C. 800°C. 300°C. F9.10 The adiabatic flame temperature of hydrocarbon fuels is 1700-2000°C. 2000-2300°C. 2300-2600°C. F10.1 The stoichiometric air to fuel mass ratio of hydrocarbon fuels is of the order of 1.5 g/g. 15 g/g. 150 g/g. F10.2 Give two examples of products of incomplete combustion that occur in fires. F10.3 Slight amounts of products of incomplete combustion are generated in overventilated fires. True False F10.4 The CO yield of a fire is a function of only the fuel involved. only the ventilation conditions. the fuel and the ventilation conditions. F10.5 A carboxyhemoglobin level of 40% in the blood is usually lethal. True (doubt) False F10.6 Carbon monoxide is the leading killer of people in fires. True False F10.7 HCN is a narcotic gas. an irritant gas. a fuel vapor. F10.8 The hazard to humans from narcotic gases is a function of only the concentration of the gas. only the duration of exposure. the product of concentration and duration of exposure. F10.9 The effects on lethality of CO, HCN, and reduced O2 are additive. True False F10.10 Irritant gases typically cause post-exposure fatalities. True False F10.11 Visibility through smoke improves with increasing optical density. True False F10.12 Heat stress occurs when the skin is exposed to a heat flux of 1 kW/m2. the skin reaches a temperature of 45°C. the body’s core temperature reaches 41°C.

F7.10 The flame spread rate through porous solids increases with concurrent wind velocity. decreases with concurrent wind velocity. is independent of concurrent wind velocity. F7.11 Surface tension accelerates opposed-flow flame spread over liquid fuels. True False F7.12 Opposed-flow flame spread rates over a solid surface are typically much smaller than 1 mm/s. around 1mm/s. much greater than 1 mm/s. F7.13 Upward flame spread rate over a vertical surface is typically between 10 and 1000 mm/s. True False F7.14 The Steiner tunnel test described in ASTM standard E 84 is used to assess the fire performance of interior finish materials based on lateral flame spread over a vertical sample. True False F8.1 Describe the triad of fire growth. F8.2 Liquid pool fires reach steady burning conditions within seconds after ignition. True False F8.3 The heat of gasification of liquid fuels is typically less than 1 kJ/g. between 1 and 3 kJ/g. greater than 3 kJ/g. F8.4 The heat flux from the flame to the surface of real burning objects can usually be determined with sufficient accuracy so that reasonable burning rate predictions can be made. True False F8.5 The mass burning flux generally associated with extinction is 0.5 g/m2s. 5 g/m2s. 50 g/m2s. F8.6 The mass burning flux of a liquid pool fire is a function of only the pool diameter. only the fuel type. pool diameter and fuel type. F8.7 The energy release rate of real objects can be measured in an oxygen bomb calorimeter. an oxygen consumption calorimeter. a room/corner test. F8.8 The peak energy release rate of typical domestic upholstered furniture can be as high as 3000 kW. True False F8.9 Draw a typical curve of the mass burning flux of a char forming fuel as a function of time. F8.10 A fast fire as defined in NFPA 72B grows proportionally to t2 and reaches an energy release rate of 1 MW in 75 sec. 150 sec. 300 sec. F9.1 Air entrainment into turbulent pool fire flames is due to buoyancy. True False F9.2 The frequency of vortex shedding in turbulent pool fire flames increases with pool diameter. decreases with pool diameter. is independent of pool diameter. F9.3 The height of turbulent jet flames for a given fuel type and orifice size is independent of energy release rate. True False F9.4 The exit velocities of fuel vapors leaving a solid or liquid pool fire surface are responsible for entrainment of air in the plume. True False F9.5 The height of a turbulent pool fire flame is a function of only energy release rate. only pool diameter. energy release rate and pool diameter. F9.6 Turbulent pool fire flame heights fluctuate in time within a factor of 2. True False F9.7 The Q* value for jet fires is 102 or greater. 104 or greater. 106 or greater. F9.8 The temperature in the continuous flame region of moderate size turbulent pool fires is approximately 820°C. True False F9.9 The temperature at the maximum flame height of a turbulent pool fire flame is approximately 1200°C. 800°C. 300°C. F9.10 The adiabatic flame temperature of hydrocarbon fuels is 1700-2000°C. 2000-2300°C. 2300-2600°C. F10.1 The stoichiometric air to fuel mass ratio of hydrocarbon fuels is of the order of 1.5 g/g. 15 g/g. 150 g/g. F10.2 Give two examples of products of incomplete combustion that occur in fires. F10.3 Slight amounts of products of incomplete combustion are generated in overventilated fires. True False F10.4 The CO yield of a fire is a function of only the fuel involved. only the ventilation conditions. the fuel and the ventilation conditions. F10.5 A carboxyhemoglobin level of 40% in the blood is usually lethal. True (doubt) False F10.6 Carbon monoxide is the leading killer of people in fires. True False F10.7 HCN is a narcotic gas. an irritant gas. a fuel vapor. F10.8 The hazard to humans from narcotic gases is a function of only the concentration of the gas. only the duration of exposure. the product of concentration and duration of exposure. F10.9 The effects on lethality of CO, HCN, and reduced O2 are additive. True False F10.10 Irritant gases typically cause post-exposure fatalities. True False F10.11 Visibility through smoke improves with increasing optical density. True False F10.12 Heat stress occurs when the skin is exposed to a heat flux of 1 kW/m2. the skin reaches a temperature of 45°C. the body’s core temperature reaches 41°C.

F7.10 The flame spread rate through porous solids increases with … Read More...
After reading the paragraph, answer the question(s) that follow. A woman has been trying to conceive for several years, unsuccessfully. At a fertility clinic, they discover that she has blocked fallopian tubes. Using modern technologies, some of her eggs are removed, fertilized with her husband’s sperm, and implanted into her uterus. The procedure is successful, but the couple discovers that their new son is color-blind and has blood type O. The woman claims that the child can’t be theirs since she has blood type A and her husband has type B. Also, neither parent is color-blind, although one grandparent (the woman’s father) is also color-blind In regard to the baby’s color blindness, a sex-linked recessive trait, you explain that

After reading the paragraph, answer the question(s) that follow. A woman has been trying to conceive for several years, unsuccessfully. At a fertility clinic, they discover that she has blocked fallopian tubes. Using modern technologies, some of her eggs are removed, fertilized with her husband’s sperm, and implanted into her uterus. The procedure is successful, but the couple discovers that their new son is color-blind and has blood type O. The woman claims that the child can’t be theirs since she has blood type A and her husband has type B. Also, neither parent is color-blind, although one grandparent (the woman’s father) is also color-blind In regard to the baby’s color blindness, a sex-linked recessive trait, you explain that

since color blindness is sex-linked, a son can inherit color … Read More...
Gordon is walking down his street, sees an angry dog running towards him, and begins to run in the opposite direction. In addition to an increase in heart rate and blood pressure, he would also display an increase in which glucocorticoid hormone? serotonin estrogen progesterone cortisol

Gordon is walking down his street, sees an angry dog running towards him, and begins to run in the opposite direction. In addition to an increase in heart rate and blood pressure, he would also display an increase in which glucocorticoid hormone? serotonin estrogen progesterone cortisol

Gordon is walking down his street, sees an angry dog … Read More...
Chapter 15 Practice Problems (Practice – no credit) Due: 11:59pm on Friday, May 16, 2014 You will receive no credit for items you complete after the assignment is due. Grading Policy Fluid Pressure in a U-Tube A U-tube is filled with water, and the two arms are capped. The tube is cylindrical, and the right arm has twice the radius of the left arm. The caps have negligible mass, are watertight, and can freely slide up and down the tube. Part A A one-inch depth of sand is poured onto the cap on each arm. After the caps have moved (if necessary) to reestablish equilibrium, is the right cap higher, lower, or the same height as the left cap? You did not open hints for this part. ANSWER: Part B This question will be shown after you complete previous question(s). Part C This question will be shown after you complete previous question(s). Part D This question will be shown after you complete previous question(s). Pressure in the Ocean The pressure at 10 below the surface of the ocean is about 2.00×105 . Part A higher lower the same height m Pa Which of the following statements is true? You did not open hints for this part. ANSWER: Part B Now consider the pressure 20 below the surface of the ocean. Which of the following statements is true? You did not open hints for this part. ANSWER: Relating Pressure and Height in a Container Learning Goal: To understand the derivation of the law relating height and pressure in a container. The weight of a column of seawater 1 in cross section and 10 high is about 2.00×105 . The weight of a column of seawater 1 in cross section and 10 high plus the weight of a column of air with the same cross section extending up to the top of the atmosphere is about 2.00×105 . The weight of 1 of seawater at 10 below the surface of the ocean is about 2.00×105 . The density of seawater is about 2.00×105 times the density of air at sea level. m2 m N m2 m N m3 m N m The pressure is twice that at a depth of 10 . The pressure is the same as that at a depth of 10 . The pressure is equal to that at a depth of 10 plus the weight per 1 cross sectional area of a column of seawater 10 high. The pressure is equal to the weight per 1 cross sectional area of a column of seawater 20 high. m m m m2 m m2 m In this problem, you will derive the law relating pressure to height in a container by analyzing a particular system. A container of uniform cross-sectional area is filled with liquid of uniform density . Consider a thin horizontal layer of liquid (thickness ) at a height as measured from the bottom of the container. Let the pressure exerted upward on the bottom of the layer be and the pressure exerted downward on the top be . Assume throughout the problem that the system is in equilibrium (the container has not been recently shaken or moved, etc.). Part A What is , the magnitude of the force exerted upward on the bottom of the liquid? You did not open hints for this part. ANSWER: Part B What is , the magnitude of the force exerted downward on the top of the liquid? A  dy y p p + dp Fup Fup = Fdown You did not open hints for this part. ANSWER: Part C What is the weight of the thin layer of liquid? Express your answer in terms of quantities given in the problem introduction and , the magnitude of the acceleration due to gravity. You did not open hints for this part. ANSWER: Part D Since the liquid is in equilibrium, the net force on the thin layer of liquid is zero. Complete the force equation for the sum of the vertical forces acting on the liquid layer described in the problem introduction. Express your answer in terms of quantities given in the problem introduction and taking upward forces to be positive. You did not open hints for this part. ANSWER: Fdown = wlayer g wlayer = Part E This question will be shown after you complete previous question(s). Part F This question will be shown after you complete previous question(s). A Submerged Ball A ball of mass and volume is lowered on a string into a fluid of density . Assume that the object would sink to the bottom if it were not supported by the string. Part A  = = i Fy,i mb V f What is the tension in the string when the ball is fully submerged but not touching the bottom, as shown in the figure? Express your answer in terms of any or all of the given quantities and , the magnitude of the acceleration due to gravity. You did not open hints for this part. ANSWER: Archimedes’ Principle Learning Goal: To understand the applications of Archimedes’ principle. Archimedes’ principle is a powerful tool for solving many problems involving equilibrium in fluids. It states the following: When a body is partially or completely submerged in a fluid (either a liquid or a gas), the fluid exerts an upward force on the body equal to the weight of the fluid displaced by the body. As a result of the upward Archimedes force (often called the buoyant force), some objects may float in a fluid, and all of them appear to weigh less. This is the familiar phenomenon of buoyancy. Quantitatively, the buoyant force can be found as , where is the force, is the density of the fluid, is the magnitude of the acceleration due to gravity, and is the volume of the displaced fluid. In this problem, you will be asked several qualitative questions that should help you develop a feel for Archimedes’ principle. An object is placed in a fluid and then released. Assume that the object either floats to the surface (settling so that the object is partly above and partly below the fluid surface) or sinks to the bottom. (Note that for Parts A through D, you should assume that the object has settled in equilibrium.) Part A Consider the following statement: The magnitude of the buoyant force is equal to the weight of fluid displaced by the object. Under what circumstances is this statement true? T g T = Fbuoyant = fluidgV Fbuoyant fluid g V You did not open hints for this part. ANSWER: Part B Consider the following statement: The magnitude of the buoyant force is equal to the weight of the amount of fluid that has the same total volume as the object. Under what circumstances is this statement true? You did not open hints for this part. ANSWER: Part C Consider the following statement: The magnitude of the buoyant force equals the weight of the object. Under what circumstances is this statement true? for every object submerged partially or completely in a fluid only for an object that floats only for an object that sinks for no object submerged in a fluid for an object that is partially submerged in a fluid only for an object that floats for an object completely submerged in a fluid for no object partially or completely submerged in a fluid You did not open hints for this part. ANSWER: Part D Consider the following statement: The magnitude of the buoyant force is less than the weight of the object. Under what circumstances is this statement true? ANSWER: Now apply what you know to some more complicated situations. Part E An object is floating in equilibrium on the surface of a liquid. The object is then removed and placed in another container, filled with a denser liquid. What would you observe? You did not open hints for this part. ANSWER: for every object submerged partially or completely in a fluid for an object that floats only for an object that sinks for no object submerged in a fluid for every object submerged partially or completely in a fluid for an object that floats for an object that sinks for no object submerged in a fluid Part F An object is floating in equilibrium on the surface of a liquid. The object is then removed and placed in another container, filled with a less dense liquid. What would you observe? You did not open hints for this part. ANSWER: Part G Two objects, T and B, have identical size and shape and have uniform density. They are carefully placed in a container filled with a liquid. Both objects float in equilibrium. Less of object T is submerged than of object B, which floats, fully submerged, closer to the bottom of the container. Which of the following statements is true? ANSWER: The object would sink all the way to the bottom. The object would float submerged more deeply than in the first container. The object would float submerged less deeply than in the first container. More than one of these outcomes is possible. The object would sink all the way to the bottom. The object would float submerged more deeply than in the first container. The object would float submerged less deeply than in the first container. More than one of these outcomes is possible. Object T has a greater density than object B. Object B has a greater density than object T. Both objects have the same density. ± Buoyant Force Conceptual Question A rectangular wooden block of weight floats with exactly one-half of its volume below the waterline. Part A What is the buoyant force acting on the block? You did not open hints for this part. ANSWER: Part B W The buoyant force cannot be determined. 2W W 1 W 2 The density of water is 1.00 . What is the density of the block? You did not open hints for this part. ANSWER: Part C This question will be shown after you complete previous question(s). Part D This question will be shown after you complete previous question(s). Part E This question will be shown after you complete previous question(s). g/cm3 2.00 between 1.00 and 2.00 1.00 between 0.50 and 1.00 0.50 The density cannot be determined. g/cm3 g/cm3 g/cm3 g/cm3 g/cm3 Flow Velocity of Blood Conceptual Question Arteriosclerotic plaques forming on the inner walls of arteries can decrease the effective cross-sectional area of an artery. Even small changes in the effective area of an artery can lead to very large changes in the blood pressure in the artery and possibly to the collapse of the blood vessel. Imagine a healthy artery, with blood flow velocity of and mass per unit volume of . The kinetic energy per unit volume of blood is given by Imagine that plaque has narrowed an artery to one-fifth of its normal cross-sectional area (an 80% blockage). Part A Compared to normal blood flow velocity, , what is the velocity of blood as it passes through this blockage? You did not open hints for this part. ANSWER: Part B This question will be shown after you complete previous question(s). Part C v0 = 0.14 m/s  = 1050 kg/m3 K0 =  . 1 2 v20 v0 80v0 20v0 5v0 v0/5 This question will be shown after you complete previous question(s). For parts D – F imagine that plaque has grown to a 90% blockage. Part D This question will be shown after you complete previous question(s). Part E This question will be shown after you complete previous question(s). Part F This question will be shown after you complete previous question(s). ± Playing with a Water Hose Two children, Ferdinand and Isabella, are playing with a water hose on a sunny summer day. Isabella is holding the hose in her hand 1.0 meters above the ground and is trying to spray Ferdinand, who is standing 10.0 meters away. Part A Will Isabella be able to spray Ferdinand if the water is flowing out of the hose at a constant speed of 3.5 meters per second? Assume that the hose is pointed parallel to the ground and take the magnitude of the acceleration due to gravity to be 9.81 meters per second, per second. You did not open hints for this part. v0 g ANSWER: Part B This question will be shown after you complete previous question(s). Tactics Box 15.2 Finding Whether an Object Floats or Sinks Learning Goal: To practice Tactics Box 15.2 Finding whether an object floats or sinks. If you hold an object underwater and then release it, it can float to the surface, sink, or remain “hanging” in the water, depending on whether the fluid density is larger than, smaller than, or equal to the object’s average density . These conditions are summarized in this Tactics Box. Yes No f avg TACTICS BOX 15.2 Finding whether an object floats or sinks Object sinks Object floats Object has neutral buoyancy An object sinks if it weighs more than the fluid it displaces, that is, if its average density is greater than the density of the fluid: . An object floats on the surface if it weighs less than the fluid it displaces, that is, if its average density is less than the density of the fluid: . An object hangs motionless in the fluid if it weighs exactly the same as the fluid it displaces. It has neutral buoyancy if its average density equals the density of the fluid: . Part A Ice at 0.0 has a density of 917 . A 3.00 ice cube is gently released inside a small container filled with oil and is observed to be neutrally buoyant. What is the density of the oil, ? Express your answer in kilograms per meter cubed to three significant figures. ANSWER: Part B Once the ice cube melts, what happens to the liquid water that it produces? You did not open hints for this part. ANSWER: avg > f avg < f avg = f 'C kg/m3 cm3 oil oil = kg/m3 Part C What happens if some ethyl alcohol of density 790 is poured into the container after the ice cube has melted? ANSWER: Score Summary: Your score on this assignment is 0%. You received 0 out of a possible total of 0 points. The liquid water sinks to the bottom of the container. The liquid water rises to the surface and floats on top of the oil. The liquid water is in static equilibrium at the location where the ice cube was originally placed. kg/m3 A layer of ethyl alcohol forms between the oil and the water. The layer of ethyl alcohol forms at the bottom of the container. The layer of ethyl alcohol forms on the surface.

Chapter 15 Practice Problems (Practice – no credit) Due: 11:59pm on Friday, May 16, 2014 You will receive no credit for items you complete after the assignment is due. Grading Policy Fluid Pressure in a U-Tube A U-tube is filled with water, and the two arms are capped. The tube is cylindrical, and the right arm has twice the radius of the left arm. The caps have negligible mass, are watertight, and can freely slide up and down the tube. Part A A one-inch depth of sand is poured onto the cap on each arm. After the caps have moved (if necessary) to reestablish equilibrium, is the right cap higher, lower, or the same height as the left cap? You did not open hints for this part. ANSWER: Part B This question will be shown after you complete previous question(s). Part C This question will be shown after you complete previous question(s). Part D This question will be shown after you complete previous question(s). Pressure in the Ocean The pressure at 10 below the surface of the ocean is about 2.00×105 . Part A higher lower the same height m Pa Which of the following statements is true? You did not open hints for this part. ANSWER: Part B Now consider the pressure 20 below the surface of the ocean. Which of the following statements is true? You did not open hints for this part. ANSWER: Relating Pressure and Height in a Container Learning Goal: To understand the derivation of the law relating height and pressure in a container. The weight of a column of seawater 1 in cross section and 10 high is about 2.00×105 . The weight of a column of seawater 1 in cross section and 10 high plus the weight of a column of air with the same cross section extending up to the top of the atmosphere is about 2.00×105 . The weight of 1 of seawater at 10 below the surface of the ocean is about 2.00×105 . The density of seawater is about 2.00×105 times the density of air at sea level. m2 m N m2 m N m3 m N m The pressure is twice that at a depth of 10 . The pressure is the same as that at a depth of 10 . The pressure is equal to that at a depth of 10 plus the weight per 1 cross sectional area of a column of seawater 10 high. The pressure is equal to the weight per 1 cross sectional area of a column of seawater 20 high. m m m m2 m m2 m In this problem, you will derive the law relating pressure to height in a container by analyzing a particular system. A container of uniform cross-sectional area is filled with liquid of uniform density . Consider a thin horizontal layer of liquid (thickness ) at a height as measured from the bottom of the container. Let the pressure exerted upward on the bottom of the layer be and the pressure exerted downward on the top be . Assume throughout the problem that the system is in equilibrium (the container has not been recently shaken or moved, etc.). Part A What is , the magnitude of the force exerted upward on the bottom of the liquid? You did not open hints for this part. ANSWER: Part B What is , the magnitude of the force exerted downward on the top of the liquid? A  dy y p p + dp Fup Fup = Fdown You did not open hints for this part. ANSWER: Part C What is the weight of the thin layer of liquid? Express your answer in terms of quantities given in the problem introduction and , the magnitude of the acceleration due to gravity. You did not open hints for this part. ANSWER: Part D Since the liquid is in equilibrium, the net force on the thin layer of liquid is zero. Complete the force equation for the sum of the vertical forces acting on the liquid layer described in the problem introduction. Express your answer in terms of quantities given in the problem introduction and taking upward forces to be positive. You did not open hints for this part. ANSWER: Fdown = wlayer g wlayer = Part E This question will be shown after you complete previous question(s). Part F This question will be shown after you complete previous question(s). A Submerged Ball A ball of mass and volume is lowered on a string into a fluid of density . Assume that the object would sink to the bottom if it were not supported by the string. Part A  = = i Fy,i mb V f What is the tension in the string when the ball is fully submerged but not touching the bottom, as shown in the figure? Express your answer in terms of any or all of the given quantities and , the magnitude of the acceleration due to gravity. You did not open hints for this part. ANSWER: Archimedes’ Principle Learning Goal: To understand the applications of Archimedes’ principle. Archimedes’ principle is a powerful tool for solving many problems involving equilibrium in fluids. It states the following: When a body is partially or completely submerged in a fluid (either a liquid or a gas), the fluid exerts an upward force on the body equal to the weight of the fluid displaced by the body. As a result of the upward Archimedes force (often called the buoyant force), some objects may float in a fluid, and all of them appear to weigh less. This is the familiar phenomenon of buoyancy. Quantitatively, the buoyant force can be found as , where is the force, is the density of the fluid, is the magnitude of the acceleration due to gravity, and is the volume of the displaced fluid. In this problem, you will be asked several qualitative questions that should help you develop a feel for Archimedes’ principle. An object is placed in a fluid and then released. Assume that the object either floats to the surface (settling so that the object is partly above and partly below the fluid surface) or sinks to the bottom. (Note that for Parts A through D, you should assume that the object has settled in equilibrium.) Part A Consider the following statement: The magnitude of the buoyant force is equal to the weight of fluid displaced by the object. Under what circumstances is this statement true? T g T = Fbuoyant = fluidgV Fbuoyant fluid g V You did not open hints for this part. ANSWER: Part B Consider the following statement: The magnitude of the buoyant force is equal to the weight of the amount of fluid that has the same total volume as the object. Under what circumstances is this statement true? You did not open hints for this part. ANSWER: Part C Consider the following statement: The magnitude of the buoyant force equals the weight of the object. Under what circumstances is this statement true? for every object submerged partially or completely in a fluid only for an object that floats only for an object that sinks for no object submerged in a fluid for an object that is partially submerged in a fluid only for an object that floats for an object completely submerged in a fluid for no object partially or completely submerged in a fluid You did not open hints for this part. ANSWER: Part D Consider the following statement: The magnitude of the buoyant force is less than the weight of the object. Under what circumstances is this statement true? ANSWER: Now apply what you know to some more complicated situations. Part E An object is floating in equilibrium on the surface of a liquid. The object is then removed and placed in another container, filled with a denser liquid. What would you observe? You did not open hints for this part. ANSWER: for every object submerged partially or completely in a fluid for an object that floats only for an object that sinks for no object submerged in a fluid for every object submerged partially or completely in a fluid for an object that floats for an object that sinks for no object submerged in a fluid Part F An object is floating in equilibrium on the surface of a liquid. The object is then removed and placed in another container, filled with a less dense liquid. What would you observe? You did not open hints for this part. ANSWER: Part G Two objects, T and B, have identical size and shape and have uniform density. They are carefully placed in a container filled with a liquid. Both objects float in equilibrium. Less of object T is submerged than of object B, which floats, fully submerged, closer to the bottom of the container. Which of the following statements is true? ANSWER: The object would sink all the way to the bottom. The object would float submerged more deeply than in the first container. The object would float submerged less deeply than in the first container. More than one of these outcomes is possible. The object would sink all the way to the bottom. The object would float submerged more deeply than in the first container. The object would float submerged less deeply than in the first container. More than one of these outcomes is possible. Object T has a greater density than object B. Object B has a greater density than object T. Both objects have the same density. ± Buoyant Force Conceptual Question A rectangular wooden block of weight floats with exactly one-half of its volume below the waterline. Part A What is the buoyant force acting on the block? You did not open hints for this part. ANSWER: Part B W The buoyant force cannot be determined. 2W W 1 W 2 The density of water is 1.00 . What is the density of the block? You did not open hints for this part. ANSWER: Part C This question will be shown after you complete previous question(s). Part D This question will be shown after you complete previous question(s). Part E This question will be shown after you complete previous question(s). g/cm3 2.00 between 1.00 and 2.00 1.00 between 0.50 and 1.00 0.50 The density cannot be determined. g/cm3 g/cm3 g/cm3 g/cm3 g/cm3 Flow Velocity of Blood Conceptual Question Arteriosclerotic plaques forming on the inner walls of arteries can decrease the effective cross-sectional area of an artery. Even small changes in the effective area of an artery can lead to very large changes in the blood pressure in the artery and possibly to the collapse of the blood vessel. Imagine a healthy artery, with blood flow velocity of and mass per unit volume of . The kinetic energy per unit volume of blood is given by Imagine that plaque has narrowed an artery to one-fifth of its normal cross-sectional area (an 80% blockage). Part A Compared to normal blood flow velocity, , what is the velocity of blood as it passes through this blockage? You did not open hints for this part. ANSWER: Part B This question will be shown after you complete previous question(s). Part C v0 = 0.14 m/s  = 1050 kg/m3 K0 =  . 1 2 v20 v0 80v0 20v0 5v0 v0/5 This question will be shown after you complete previous question(s). For parts D – F imagine that plaque has grown to a 90% blockage. Part D This question will be shown after you complete previous question(s). Part E This question will be shown after you complete previous question(s). Part F This question will be shown after you complete previous question(s). ± Playing with a Water Hose Two children, Ferdinand and Isabella, are playing with a water hose on a sunny summer day. Isabella is holding the hose in her hand 1.0 meters above the ground and is trying to spray Ferdinand, who is standing 10.0 meters away. Part A Will Isabella be able to spray Ferdinand if the water is flowing out of the hose at a constant speed of 3.5 meters per second? Assume that the hose is pointed parallel to the ground and take the magnitude of the acceleration due to gravity to be 9.81 meters per second, per second. You did not open hints for this part. v0 g ANSWER: Part B This question will be shown after you complete previous question(s). Tactics Box 15.2 Finding Whether an Object Floats or Sinks Learning Goal: To practice Tactics Box 15.2 Finding whether an object floats or sinks. If you hold an object underwater and then release it, it can float to the surface, sink, or remain “hanging” in the water, depending on whether the fluid density is larger than, smaller than, or equal to the object’s average density . These conditions are summarized in this Tactics Box. Yes No f avg TACTICS BOX 15.2 Finding whether an object floats or sinks Object sinks Object floats Object has neutral buoyancy An object sinks if it weighs more than the fluid it displaces, that is, if its average density is greater than the density of the fluid: . An object floats on the surface if it weighs less than the fluid it displaces, that is, if its average density is less than the density of the fluid: . An object hangs motionless in the fluid if it weighs exactly the same as the fluid it displaces. It has neutral buoyancy if its average density equals the density of the fluid: . Part A Ice at 0.0 has a density of 917 . A 3.00 ice cube is gently released inside a small container filled with oil and is observed to be neutrally buoyant. What is the density of the oil, ? Express your answer in kilograms per meter cubed to three significant figures. ANSWER: Part B Once the ice cube melts, what happens to the liquid water that it produces? You did not open hints for this part. ANSWER: avg > f avg < f avg = f 'C kg/m3 cm3 oil oil = kg/m3 Part C What happens if some ethyl alcohol of density 790 is poured into the container after the ice cube has melted? ANSWER: Score Summary: Your score on this assignment is 0%. You received 0 out of a possible total of 0 points. The liquid water sinks to the bottom of the container. The liquid water rises to the surface and floats on top of the oil. The liquid water is in static equilibrium at the location where the ice cube was originally placed. kg/m3 A layer of ethyl alcohol forms between the oil and the water. The layer of ethyl alcohol forms at the bottom of the container. The layer of ethyl alcohol forms on the surface.

please email info@checkyourstudy.com Chapter 15 Practice Problems (Practice – no … Read More...
Which is NOT a association of brain structures and functions? Select one: a. midbrain—reflex centers for visual, auditory, and tactile responses b. cerebellum—coordinates smooth and coordinated motions c. cerebrum—higher thought processes including learning, memory, and speech d. pons—regulates breathing rate e. thalamus—regulates heartbeat and blood pressure

Which is NOT a association of brain structures and functions? Select one: a. midbrain—reflex centers for visual, auditory, and tactile responses b. cerebellum—coordinates smooth and coordinated motions c. cerebrum—higher thought processes including learning, memory, and speech d. pons—regulates breathing rate e. thalamus—regulates heartbeat and blood pressure

Info@checkyourstudy.com                                                                                                                                                                                       : thalamus—regulates heartbeat and blood pressure
During organ transplant, which feature is the most important to recognize? Select one: a. The difference between the MHC proteins of the donor and the recipient. b. The difference between the blood types of the donor and the recipient. c. The similarities between the blood types of the donor and the recipient. d. The type of organ being transplanted. e. The age of the recipient of the transplanted organ.

During organ transplant, which feature is the most important to recognize? Select one: a. The difference between the MHC proteins of the donor and the recipient. b. The difference between the blood types of the donor and the recipient. c. The similarities between the blood types of the donor and the recipient. d. The type of organ being transplanted. e. The age of the recipient of the transplanted organ.

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1. A biological psychologist would be most interested in conducting research on the relationship between A) neurotransmitters and depression. B) bone density and body size. C) self-esteem and popularity. D) genetics and eye color. 2. The function of dendrites is to A) receive incoming signals from other neurons. B) release neurotransmitters into the spatial junctions between neurons. C) coordinate the activation of the parasympathetic and sympathetic nervous systems. D) control pain through the release of opiate-like chemicals into the brain. 3. Sensory neurons are located in the A) thalamus. B) reticular formation. C) peripheral nervous system. D) sensory cortex. 4. The part of the brainstem that controls heartbeat and breathing is called the A) cerebellum. B) medulla. C) amygdala. D) thalamus. 5. After flying from California to New York, Arthur experienced a restless, sleepless night. His problem was most likely caused by a disruption of his normal A) change blindness. B) circadian rhythm. C) hypnagogic sensations. D) sleep paralysis. 6. Mr. Oates always sleeps restlessly, snorting and gasping throughout the night. It is most likely that Mr. Oates suffers from A) sleep apnea. B) narcolepsy. C) night terrors. D) insomnia. 7. A condition in which a person can respond to a visual stimulus without consciously experiencing it is known as A) narcolepsy. B) change blindness. C) REM rebound. D) blindsight. 8. Consciousness is to unconsciousness as ________ is to ________. A) tolerance; withdrawal B) sequential processing; parallel processing C) latent content; manifest content D) delta wave; alpha wave 9. Auditory stimulation is first processed in the ________ lobes. A) occipital B) temporal C) frontal D) parietal 10. Acetylcholine is a neurotransmitter that A) causes sleepiness. B) lessens physical pain. C) reduces depressed moods. D) triggers muscle contractions. 11. Which of the following is not one of the phases of the general adaptation syndrome: A) attention B) alarm reaction C) resistance D) exhaustion 12. People with Type B personality A) Are at a greater risk for heart disease B) Tend to be more easy-going than those with Type A personality C) Are at a greater risk for depression D) Tend to be more motivated to do well than those with Type A personality 13. Which is an example of problem-focused coping A) Studying harder for an exam after you got a bad grade on the first one B) Trying not to think about how angry you are C) Distracting yourself by watching a funny movie D) Talking about how upset you are with your friend 14. People with an external locus of think that A) events are largely outside of their control B) too much personal freedom decreases life satisfaction. C) individuals can influence their own outcomes in life. D) self-control gets permanently weaker with age 15. Which of the following is a benefit of social support A) improved immune system functioning B) decreased blood pressure C) improved health D) all of the above

1. A biological psychologist would be most interested in conducting research on the relationship between A) neurotransmitters and depression. B) bone density and body size. C) self-esteem and popularity. D) genetics and eye color. 2. The function of dendrites is to A) receive incoming signals from other neurons. B) release neurotransmitters into the spatial junctions between neurons. C) coordinate the activation of the parasympathetic and sympathetic nervous systems. D) control pain through the release of opiate-like chemicals into the brain. 3. Sensory neurons are located in the A) thalamus. B) reticular formation. C) peripheral nervous system. D) sensory cortex. 4. The part of the brainstem that controls heartbeat and breathing is called the A) cerebellum. B) medulla. C) amygdala. D) thalamus. 5. After flying from California to New York, Arthur experienced a restless, sleepless night. His problem was most likely caused by a disruption of his normal A) change blindness. B) circadian rhythm. C) hypnagogic sensations. D) sleep paralysis. 6. Mr. Oates always sleeps restlessly, snorting and gasping throughout the night. It is most likely that Mr. Oates suffers from A) sleep apnea. B) narcolepsy. C) night terrors. D) insomnia. 7. A condition in which a person can respond to a visual stimulus without consciously experiencing it is known as A) narcolepsy. B) change blindness. C) REM rebound. D) blindsight. 8. Consciousness is to unconsciousness as ________ is to ________. A) tolerance; withdrawal B) sequential processing; parallel processing C) latent content; manifest content D) delta wave; alpha wave 9. Auditory stimulation is first processed in the ________ lobes. A) occipital B) temporal C) frontal D) parietal 10. Acetylcholine is a neurotransmitter that A) causes sleepiness. B) lessens physical pain. C) reduces depressed moods. D) triggers muscle contractions. 11. Which of the following is not one of the phases of the general adaptation syndrome: A) attention B) alarm reaction C) resistance D) exhaustion 12. People with Type B personality A) Are at a greater risk for heart disease B) Tend to be more easy-going than those with Type A personality C) Are at a greater risk for depression D) Tend to be more motivated to do well than those with Type A personality 13. Which is an example of problem-focused coping A) Studying harder for an exam after you got a bad grade on the first one B) Trying not to think about how angry you are C) Distracting yourself by watching a funny movie D) Talking about how upset you are with your friend 14. People with an external locus of think that A) events are largely outside of their control B) too much personal freedom decreases life satisfaction. C) individuals can influence their own outcomes in life. D) self-control gets permanently weaker with age 15. Which of the following is a benefit of social support A) improved immune system functioning B) decreased blood pressure C) improved health D) all of the above

The correct answer has an “*” in front of it. … Read More...
Activation of this hormone increases blood pressure by causing the blood vessels to constrict and the kidneys to retain more water. Question 5 options: neuropeptide Y adrenocorticotropic hormone hypothalamic-pituitary-adrenal axis antidiuretic hormone

Activation of this hormone increases blood pressure by causing the blood vessels to constrict and the kidneys to retain more water. Question 5 options: neuropeptide Y adrenocorticotropic hormone hypothalamic-pituitary-adrenal axis antidiuretic hormone

Activation of this hormone increases blood pressure by causing the … Read More...
During chronic stress conditions, this chemical causes vasoconstriction and may contribute to the increase in chronic blood pressure associated with long-term stress. Question 3 options: neuropeptide Y adrenocorticotropic hormone hypothalamic-pituitary-adrenal axis antidiuretic hormone

During chronic stress conditions, this chemical causes vasoconstriction and may contribute to the increase in chronic blood pressure associated with long-term stress. Question 3 options: neuropeptide Y adrenocorticotropic hormone hypothalamic-pituitary-adrenal axis antidiuretic hormone

During chronic stress conditions, this chemical causes vasoconstriction and may … Read More...
Prostaglandins can sometimes cause a reduction in the normal blood flow to the uterus, and this condition is called: Question 42 options: Intermenstrual bleeding Cryptomenorrhea Uterine ischemia Adenomyosis

Prostaglandins can sometimes cause a reduction in the normal blood flow to the uterus, and this condition is called: Question 42 options: Intermenstrual bleeding Cryptomenorrhea Uterine ischemia Adenomyosis

Prostaglandins can sometimes cause a reduction in the normal blood … Read More...