Air resistance

An alternative method for measuring air permeabiUty is based on measuring differential pressure when a constant rate of air flow passes through the fabric. In this case, air resistance is reported in typical units of kPa-s/m. 

This equation does, of course, assume that all the potential energy is converted into useful work. This is impossible in practice because some work will be done against friction - in wheel bearings, tyres and air resistance - and the free work must really be written as... 

To prevent the surrounding air from mixing with the supply air, the air shower should use air-permeable filter material with a harder, load-bearing, nonflammable outer shell and an inner layer of softer material with a high air resistance. This design requires that the supplied air be filtered. 

Luft-bestandigkeit, /. stability in air, resistance to air. -bestandteil, m. constituent of air. -bild, n. aerial photograph (Optica) aerial image, -blaschen, n. (small) air bubble, -blase,/, air bubble air pocket air bladder, -bleiche, /. open-air bleaching, -bombe, /. aerial bomb, -brennstoffgemisch, n. fuel-air mixture. 

Of course, the air is rarely still, just as the ground is rarely flat. Tail winds do speed the rider, but headwinds have a direct effect on the rider s speed, too A rider traveling at 20 mph into a 15 mph (24 kph) headwind encounters as much air resistance as a rider traveling at 35 mph (56 kph) under windless conditions. A head wind will slow one dovni by half its o wn speed. If one normally rides 15 mph, and then steers into a 10 mph headwind, the resulting speed tvill be 10 mph. 

A simple pendulum isolated from nonconseiwative forces would oscillate forever. Complete isolation can never be achieved, and the pendulum will eventually stop because nonconsewative forces such as air resistance and surface friction always remove mechanical energy from a system. Unless there is a mechanism for putting the energy back, the mechan-... 

It can be welded by resistance, tungsten-inert gas (TIG), plasma arc and electron beam techniques. To protect the metal from attack by air, resistance welding is carried out under water and the TIG method is best performed in a chamber of argon. The latter three methods produce ductile welds that equal the base metal in most of its characteristics. 

As a filter element collects dust, the air resistance through it will rise, to a point where the system air flow is impaired. Users need to have an objective indication of this limit, and all filters except those on small package units should be fitted with manometers (see Figure 2 7.2). On installation, marks should be set to indicate clean and dirty resistance pressure levels. 

Muzzle Velocity (MV, Initial Velocity). The velocity at which a projectile leaves the muzzle of a gun, expressed either in m/sec or ft/sec. The moment the projectile emerges from the bore, its velocity starts to decrease because of air resistance. For this reason, the muzzle velocity is considered as the max velocity of a... 

Here Ac = Ca - XhCw with Cg and Cw representing the concentrations in the air and water respectively and Kh the Henry s law constant. The parameter K, linking the flux and the concentration difference, has the dimension of a velocity. It is often referred to as the transfer (or piston) velocity. The reciprocal of the transfer velocity corresponds to a resistance to transfer across the surface. The total resistance R — K ) can be viewed as the sum of an air resistance (i a) and a water resistance (Rw). ... 

The tire constmction influences both cornering and longitudinal slip stiffness. These include the tire carcass, breaker construction, inflation pressure, and tread pattern design. However, since the two stiffness components can be measured, knowledge of the construction details is not necessary. The vehicle geometry influences the tire wear through the air resistance, which it creates, and through the load distribution between front and rear axles. 

During its motion the mass experiences a resistance, caused by different factors, in particular, by air. This force of air resistance opposes the motion and it is directly proportional to the velocity ... 

Robert Richards Well we ve learned what the explanation is. The maternal attachment would seem to be the fact. Now we want an explanation or an account of it. Now a lot of explanations in science have that character that you said to know that heavy bodies fall faster than lighter bodies, which is of course true of air resistance and so forth, but to understand the principles of fall does seem to have. .. 

The filter material should consist of peat mixed with heather in order to keep the air resistance low. If the peat filter is to give maximum odour reduction the peat must be moist. 

In order to keep the operating costs as low as possible the filter is dimensioned in such a way that the air resistance will be low. Naturally, the flow resistance is highly dependent on the filter material and the air speed through the filter. According to Zeisig, the filter area should be 25m2 per 100 pigs. The filter material should consist of peat mixed with heather. A suitable mixture is considered to be ca 50% peat and 50% heather calculated... 

Charlie Brown and Snoopy are sledding down a hiU that is inclined 6 degrees from horizontal. The total weight of Charhe, Snoopy, and the sled is M. The sled is essentially fiictionless but the air resistance of the sledders is proportional to the square of their velocity. Write the equations describing their position x, relative to the top of the hiU (x = 0). Charhe tikes to belly flop, so their initial velocity at the top of the hill is Pq. ... 

What would happen if Snoopy jumped off the sled halfway down the hiU without changing the air resistance ... 

Assume that the car was fricLionless and encountered negligible air resistance, (a) At what distance down the hill did Sam s brakes burn up ... 

J. Dufour, J. Huot, Rapid activation, enhanced hydrogen sorption kinetics and air resistance in laminated Mg-Pd 2.5at.%, J. Alloys Compd. 439 (2007) L5-L9. 

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