state of matter - Mayfield City Schools
... substance to a higher-temperature substance (You can’t break even; you can’t return to the same energy state because entropy always increases). -When heat flow is spontaneous (without the assistance of external work), the direction of the flow is always from hot to cold. Heat can be made to flow the ...
... substance to a higher-temperature substance (You can’t break even; you can’t return to the same energy state because entropy always increases). -When heat flow is spontaneous (without the assistance of external work), the direction of the flow is always from hot to cold. Heat can be made to flow the ...
Lecture 2 Intro to Heat Flow
... Lecture 2 Intro to Heat Flow Surface heat flow Heat flux from the Sun (mostly reradiated): 400 W/m2 Heat flux from Earth’s interior: 80 mW/m2 Earthquake energy loss: 0.2 mW/m2 Heat flow from human? energy intake: 2000 “calories” ≈ 8000 kJ (W = J/s) 8000 kJ / 24 hr = ~100 J/s = 100 W (1 day ≈ 80,000 ...
... Lecture 2 Intro to Heat Flow Surface heat flow Heat flux from the Sun (mostly reradiated): 400 W/m2 Heat flux from Earth’s interior: 80 mW/m2 Earthquake energy loss: 0.2 mW/m2 Heat flow from human? energy intake: 2000 “calories” ≈ 8000 kJ (W = J/s) 8000 kJ / 24 hr = ~100 J/s = 100 W (1 day ≈ 80,000 ...
ANIMAL FORM & FUNCTION
... The majority of cell in most animals (all but sponges and cnidarians) are not exposed to the external environment, but are bathed by an extracellular fluid. Animals with an open circulatory system have an extracellular compartment containing hemolymph which bathes the cells. Animals with a clo ...
... The majority of cell in most animals (all but sponges and cnidarians) are not exposed to the external environment, but are bathed by an extracellular fluid. Animals with an open circulatory system have an extracellular compartment containing hemolymph which bathes the cells. Animals with a clo ...
Quiz Review Name Period 1. What is the equation that
... 15. When a substance condenses, the particles starts to slow down / speed up. 16. When a substance undergoes sublimation, it gets pulled together / separated. 17. Which of the following substance will have the lowest temperature after an hour of being in the sun? Water (4.184 J/goC) ...
... 15. When a substance condenses, the particles starts to slow down / speed up. 16. When a substance undergoes sublimation, it gets pulled together / separated. 17. Which of the following substance will have the lowest temperature after an hour of being in the sun? Water (4.184 J/goC) ...
Thermodynamics
... number of moles is often a helpful method. Letter C refers to the molar specific heat capacity. Use Kelvin as the unit for temperature. Cp and Cv must be used depending on constant pressure or volume conditions. ...
... number of moles is often a helpful method. Letter C refers to the molar specific heat capacity. Use Kelvin as the unit for temperature. Cp and Cv must be used depending on constant pressure or volume conditions. ...
The Excretory System 38-3
... The urinary bladder is a saclike organ where urine is stored The functional parts of the kidney are called nephrons, they filter out impurities from the blood ...
... The urinary bladder is a saclike organ where urine is stored The functional parts of the kidney are called nephrons, they filter out impurities from the blood ...
Evaporation
... & heat loss Heat gain (all sources) must equal heat lost (all modes). of At air temperature >34 o C, radiation and metabolism are main sources of gain and evaporation is main heat loss. At air temperature <20 o C, metabolism is main heat gain and radiation is main heat loss. ...
... & heat loss Heat gain (all sources) must equal heat lost (all modes). of At air temperature >34 o C, radiation and metabolism are main sources of gain and evaporation is main heat loss. At air temperature <20 o C, metabolism is main heat gain and radiation is main heat loss. ...
Countercurrent exchange
Countercurrent exchange is a mechanism occurring in nature and mimicked in industry and engineering, in which there is a crossover of some property, usually heat or some component, between two flowing bodies flowing in opposite directions to each other. The flowing bodies can be liquids, gases, or even solid powders, or any combination of those. For example, in a distillation column, the vapors bubble up through the downward flowing liquid while exchanging both heat and mass.The maximum amount of heat or mass transfer that can be obtained is higher with countercurrent than co-current (parallel) exchange because countercurrent maintains a slowly declining difference or gradient (usually temperature or concentration difference). In cocurrent exchange the initial gradient is higher but falls off quickly, leading to wasted potential. For example, in the diagram at the right, the fluid being heated (exiting top) has a higher exiting temperature than the cooled fluid (exiting bottom) that was used for heating. With cocurrent or parallel exchange the heated and cooled fluids can only approach one another. The result is that countercurrent exchange can achieve a greater amount of heat or mass transfer than parallel under otherwise similar conditions. See: flow arrangement.Countercurrent exchange when set up in a circuit or loop can be used for building up concentrations, heat, or other properties of flowing liquids. Specifically when set up in a loop with a buffering liquid between the incoming and outgoing fluid running in a circuit, and with active transport pumps on the outgoing fluid's tubes, the system is called a Countercurrent multiplier, enabling a multiplied effect of many small pumps to gradually build up a large concentration in the buffer liquid.Other countercurrent exchange circuits where the incoming and outgoing fluids touch each other are used for retaining a high concentration of a dissolved substance or for retaining heat, or for allowing the external buildup of the heat or concentration at one point in the system.Countercurrent exchange circuits or loops are found extensively in nature, specifically in biologic systems. In vertebrates, they are called a Rete mirabile, originally the name of an organ in fish gills for absorbing oxygen from the water. It is mimicked in industrial systems. Countercurrent exchange is a key concept in chemical engineering thermodynamics and manufacturing processes, for example in extracting sucrose from sugar beet roots.Countercurrent multiplication is a similar but different concept where liquid moves in a loop followed by a long length of movement in opposite directions with an intermediate zone. The tube leading to the loop passively building up a gradient of heat (or cooling) or solvent concentration while the returning tube has a constant small pumping action all along it, so that a gradual intensification of the heat or concentration is created towards the loop. Countercurrent multiplication has been found in the kidneys as well as in many other biological organs.