What is air resistance?
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the resistive force that air will exert upon an object moving through it at a given velocity.\n\nthe equation is Drag= 1/2 cpav2 (squared)\n\nc is a constant.\np is the density of the fluid (air in this case)\na is the cross sectional area of the object\nv is the velocity of the object.
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cfm. Cubic feet per minute, a measure of air flow
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AIR, WOOD,  stone, (insulation)\n\nR-value\nThe R-value of a material is its resistance to heat flow and is an indication of its ability to insulate. It is used as a standard way of telling how good a material will insulate.The higher the R-value, the better the insulation.\n\nDefinition\nThe R-value is the reciprocal of the amount of heat energy per area of material per degree difference between the outside and inside. Its units of measurement for R-value are:\n\n(square feet x hour x degree F)/BTU in the English system and\n\n(square meters x degrees C)/watts in the metric system\n\n\n\nMaterial\n R-value\n \nHardwood siding (1 in. thick)\n 0.91\n \nWood shingles (lapped)\n 0.87\n \nBrick (4 in. thick)\n 4.00\n \nConcrete block (filled cores)\n 1.93\n \nFiberglass batting (3.5 in. thick)\n 10.90\n \nFiberglass batting (6 in. thick)\n 18.80\n \nFiberglass board (1 in. thick)\n 4.35\n \nCellulose fiber (1 in. thick)\n 3.70\n \nFlat glass (0.125 in thick)\n 0.89\n \nInsulating glass (0.25 in space)\n 1.54\n \nAir space (3.5 in. thick)\n 1.01\n \nFree stagnant air layer\n 0.17\n \nDrywall (0.5 in. thick)\n 0.45\n \nSheathing (0.5 in. thick)\n 1.32
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Ventilation - the physical act of moving air in and out of the lungs.\n\na)  Passage way resistent would reduce the volume of air that could be inspired - either by hyperinflating the lungs thereby not allowing new air to fill the lungs with breathing OR by the simple resistence itself, no allowing air in (but its usually the former).\n\nb) Decrease lung compliance would reduce the inspiratory volume and therefore decrease ventilation.\n\nc)  If the lungs did not secrete surfactant, the surface tension of alveoli would be much higher and it would not be able to inflate normally.  Therefore ventilation would be reduced again.\n\nSo after I help you with your homework, are you going to buy me lunch?
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Resistance is the property in an electrical circuit.\n\nAny wire will have some resistance to flow of charges.\n\nThe property that gives hindrance to flow of charges is called resistance.\n\nIf there is any obstacle to the flow of charges then the one which gives this obstacle is said to possess some resistance.\n\nThe resistance is related by this simple equation E = I R.\n\nOr R = E/I. \n\nE is the potential difference and I is the rate of flow of charges.\n\nThe resistance is zero only when I is infinity.\n\nThe resistance is less when I is great for small values of E.\n\nThe resistance is large when I is small for a value of E.\n\nThe potential difference between the ends of a battery is full to its maximum when it is not connected to any external circuit.\n\nThat is when the current is zero the potential difference across the battery is maximum. This maximum potential difference is called E.M.F of the battery\n\nConsider a battery of 2 Volt.\n\nWhen this is connected to a resistor of 2 Ohm the current we expect is 2/2 = 1 ampere. \n\nBut in practice this will not happen.\n\nThe current will be less than 1A. Suppose that the current is 0. 95 A.\n\nAt the same time if we measure the potential difference it will NOT be 2 volt but it will be only 1.9 volt. \n\nThus there is a loss of 0.1 volt.\n\nThe chemicals inside the battery produce this 0.1 volt opposing the 2 volt ( when there is no flow of charges inside the battery).\n\n\n \n\nReturning to the current consideration, we used a battery of 2 volt E.MF and a resistor of resistance 2 ohm. But the current is 0.95 A instead of 1 A.\n\nIf the total resistance were 2.105 ohm instead of 2 ohm , then the current in the circuit will be 2 / 2.105 = 0.95 A.\n\nThus we see that the battery is having some INTERNAL resistance of 0.105 ohm.\n\nThis resistance is due to the production of opposite emf of 0.1 volt to the actual emf of 2 volt (2- 01 = 1.9 V). The potential difference across the battery has reduced to 1.9V from 2 V.\n\nThus the resistance is only a property and there not be any resistor inside the battery.\n\nThis internal resistance is not a constant one and will vary according to the external resistances used in the circuit and other factors.
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velocity-height and horizontal movement. 11.2 km/s in order to escape earth's atmosphere (air provides resistance against movement) above 50 km and movement in horizontal direction so that the object falls perpetually towards the earths gravity centre.
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if u recollect the equation,\n             resistance (r)= pl/A;\n        where p=specific resistivity\n                   l= length\n                   A= cross sectional area \n               Area = pie(3.414) * r2\n                  \n              but diameter is twic the radius.\nhence insulation thickness is dependent on pipe diameter.
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neglecting air resistance I hope!\n\ny=1/2at^2+vot+yo\n\na=32 ft/sec^2   you did mean sec^2?\n\nalso, v=at+vo  so we can find vo from this at time 2.1s when v=0\n\nfinally we insert 2.9 s into the first equation (yo= 0 too right?).
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The ball will reach a maximum height, then the velocity of gravity (9.8 meters/second) would cause it to travel downward until another force acts upon it (according to Newton's laws of motion). However, this does not account for other forces, such as air resistance. The rate at which the ball falls and the air resistance acting upon it will depend on the properties of the ball (surface area, weight, etc.). If the ball is inside a vacuum, it is said to be in free fall (as the only force acting upon it is gravity) and there is no other force acting upon it. If the ball is allowed to fall long enough, it will reach a point of terminal velocity, where it cannot fall any faster (the force of air resistance will equal the weight of the object)
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What type of resistance--thermal, electral, or what?\n\nBoth are generally determined by the bandwidth of free electrons if any are present.  In electrical, it can also deal with impurities in the material.  In thermal, it can have to do with the irregularity of the molecular structure, the density of the solid, and the heat capacity of the molecules.
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Wikipedia of course\nhttp://en.wikipedia.org/wiki/Air
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The object will follow a parabolic trajectory to the earth, as observed from outside the plane.  On the plane, it will appear to fall straight down in your (moving) frame of reference.  Air resistance will retard this motion, but it's magnitude depends on the drag coefficient of the object dropped and the medium in which it is falling.
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An ampere is a measure of current -- how much electricity is passing through your wire at any given time.  An ohm is a measure of resistance -- how much is the wire resisting the flow electricity through the wire.  Although many electrical engineers frown on this analogy, I find it useful: Think of your wire as a big garden hose.  You turn on the water and charge the hose.  The water pressure is kind of analogous to voltage -- it's the difference between the pressure at the source and the open end of the hose, and is a measure of potential between the two points.  Amperage is kind of like flow rate -- how many gallons a minute are you getting out of that hose?  And resistance is a measure of the friction slowing the flow down, as well as any back-pressure if you stuck your finger over the end or if the hose develops a kink.  If you got a bigger hose, you could obviously move more water and it is less likely to get constricted (thicker wire means it can handle more amps, and has less resistance to flow) but you'd have to have a bigger pressure source to push that much water through it (needs a higher voltage to maintain the same level of current through a thicker wire)  Does that help?
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You can call it wind resistance or skin friction.
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The density of air, ρ (Greek: rho) (air density), is the mass per unit volume of Earth's atmosphere, and is a useful value in aeronautics. In the SI system it is measured as the number of kilograms of air in a cubic meter (kg/m3). At sea level and at 20 °C dry air has a density of approximately 1.2 kg/m3. varying with pressure and temperature. Air density and air pressure decrease with increasing altitude.\n\nThe formula for the density of air is given by:\n\n P=p/R*T\nwhere ρ is the air density, p is pressure, R is the gas constant, and T is temperature.\n\nThe individual gas constant R for dry air is:\n\n R( dry air )=287.05J/kg*K\nTherefore:\n\nAt standard temperature and pressure (0 °C and 101.325 kPa), dry air has a density of ρSTP = 1.293 kg/m3. \nAt standard ambient temperature and pressure (25 °C and 100 kPa) dry air has a density of ρSATP = 1.168 kg/m3. \n[edit]\nEffect of water vapor\nFor moist air, the partial pressure of the water vapor must be considered as well. In this case, the density of the air is the sum of the density of the dry air and the density of the water vapor:\nP=pdry air /Rdry air*T+p water vapour/R water vapour*T\n \nThe gas constant for water vapor is:\nR water vapour=461.495 J/kg*K\n \nEffects of altitude\nTo calculate the density of air as a function of altitude, one requires additional parameters. They are listed below, along with their values according to the International Standard Atmosphere, using the universal gas constant instead of the specific one:\n\nsea level atmospheric pressure p0 = 101325 Pa = 1013.25 mbar or hPa = 101.325 kPa (= 101325 kg/(m*s2)) \nsea level standard temperature T0 = 288.15 K \nEarth-surface gravitational acceleration g = 9.80665 m/s2. \ndry adiabatic lapse rate L = −0.0065 K/m \nuniversal gas constant R = 8.31447 J/(mol·K) \nmolecular weight of dry air M = 0.0289644 kg/mol \nTemperature at altitude h metres above sea level is given by the following formula (only valid below the tropopause):\n\n T=To+L*H\nImportance of temperature\nThe below table demonstrates that the properties of air change significantly with temperature.\n\nTable — speed of sound in air c, density of air ρ, acoustic impedance Z vs. temperature °C\n\nImpact of temperature \n°C c in m/s ρ in kg/m³ Z in Pa·s/m \n- 10 325.4 1.341 436.5 \n- 5 328.5 1.316 432.4 \n0 331.5 1.293 428.3 \n+ 5 334.5 1.269 424.5 \n+ 10 337.5 1.247 420.7 \n+ 15 340.5 1.225 417.0 \n+ 20 343.4 1.204 413.5 \n+ 25 346.3 1.184 410.0 \n+ 30 349.2 1.164 406.6
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Technically, it is the vapor pressure of water in the air divided by the saturation pressure at a given temperature.\n\nIn plain English, it is the fraction of water in air at some temperature vs the maximum amount of water that could be in the air at that temperature.\n\nIt varies with temperature because water's vapor pressure (the amount of water that can evaporate) rises with temperature.\n\nHope that helps.
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Electrical resistance is that element of electrical circuit which opposes flow of current through it.\n1.Resistance is dependent on the material.Like wood is insulator(ALMOST infinite resistance).\n2.Resistance of a wire having more cross sectional area is less and less cross sectional area is more(i.e. it is inversely propotional to the cross sectional area.)\n3.It is more for more length and less for less length.\n4. Resistance varies with temprature.For metals like platinum it increses with temprature.