Say’s Law

There are three main consequences of this separation of purchase from sale. The first is a critique of Ricardo s assertion that no man produces but with a view to consume or sell (Ricardo 1951 290 see Kenway 1980 28). Instead of a separation of purchase from sale, Ricardo assumes each individual is simultaneously a producer and consumer, deciding what to produce and consume in the same breath. This is Say s Law, that supply creates its own demand. Marx was very scathing about Say s Law, viewing it as childish babble and a cosy description of bourgeois conditions (Marx 1969b 502-3). From a class-based perspective, there is a demarcation between the production decisions of a small number of capitalists and the consumption decisions of the population as a whole. 

This Domar interpretation can be placed in stark contrast to the argument made by Shoul (2000 98) that Marx s reproduction models postulate the operation of Say s Law (see also Robinson 1968 111). The argument,... 

As we have seen, however, the circulation of money also plays a pivotal role in the reproduction schema. Without borrowing from the financial system expanded reproduction is not possible. Investment is exogenous, financed not out of the pockets of capitalists, but by the financial system. Embedded in the tension, established by Domar, between investment as a dual source of capacity and demand, is a fragile network of credit relationships between capitalists and banks. Marx s reproduction schemes expose the stringent conditions on the finance and realization of investment that are required for balanced growth. Since these conditions are unlikely to be met - supply is unlikely to create its own demand - a refutation of Say s Law is offered by the reproduction schema. 

Shoul s main motivation is to demonstrate the power of Marx s tendency of the falling rate of profit, which in her view operates even when Say s Law is postulated, even when questions of demand are assumed away (see Shoul 2000 28). Further consideration of this issue is provided in Chapter 7, where it is argued that realization problems are in fact central to Marx s falling rate of profit thesis. 

Shoul, B. (2000) Karl Marx and Say s Law , in J. Cunningham Wood and S. Kates (eds) Jean-Baptiste Say Critical Assessments of Leading Economists vol. 5, London Routledge, pp. 94-111, 1957. 

Jean-Baptiste Say (1767-1832), French economist famous for formulating Say s Law, wiiich states that the supply of some goods creates its own demand. The fullest account of his views is to be found in his Traite d economique politique (Paris, 1806). - Eds. 

It should be noted that, whatever the fonu of Henry s law (i.e. in whatever composition units), Raoult s law must necessarily be expressed in mole fraction. This says nothing about the appropriateness of mole fractions in condensed systems, e.g. in equilibrium expressions it arises simply from the fact that it is a statement about... 

According to Bernoulli s Law, when velocity goes up, pressure goes down. This was explained in Chapter 1. A centrifugal pump works by acceleration and imparting velocity to the liquid in the eye of the impeller. Under the right conditions, the liquid can boil or vaporize in the eye of the impeller. When this happens we say that the pump is suffering from vaporization cavitation. 

The other ease is when there is too niiieh flow through the pump. The pump is operating to the right of the BEP on its eurve (Figure 9-8). The same problem oceurs, but now in the other direction. With the severe increase in velocity through the pump, the pressures tall dramatically in the H-F-G-H arc of the volute circle (Bernoulli s Law-says that as velocity goes up, pressure comes down). Now the shaft deflects, or even breaks in the opposite direction. .. at approximately 240° around the volute from the cutwater. 

An attempt to forecast the further shrinkage of integrated circuits has been made by Gleason (2000). He starts out with some up-to-date statistics during the past 25 years, the number of transistors per unit area of silicon has increased by a factor of 250, and the density of circuits is now such that 20,000 cells (each with a transistor and capacitor) would fit within the cross-section of a human hair. This kind of relentless shrinkage of circuits, following an exponential time law, is known as Moore s law (Moore was one of the early captains of this industry). The question is whether the operation of Moore s Law will continue for some years yet Gleason says that attempts to forecast an end to the validity of Moore s Law have failed dismally it has continued to hold well beyond expectations . The problems at... 

Go to a standard handbook like Perry s Chemical Engineer s Handbook and obtain several hydraulic conductivities (say for sand, crushed stone, gravel, diatomaceous earth, other). Assume a constant head of fluid over a bed of each material, and apply Darcy s law to calculate flowrates and compare the results. Try several hydraulic head calculations and plot the results. Which of the materials studied shows the highest hydraulic resistance ... 

In accordance with Ohm s law, if we were to double the intensity X of the electric field, the current would be doubled that is to say, the plane CD would have to be placed at twice the distance from AB. If the number of conduction electrons per unit volume is p, and the distance between the planes CD and AB is denoted by v, we have n = pv, since we are discussing the unit area. Hence the net resultant charge transported in unit time across AB, that is, the current density, is given by... 

For solutions which do not follow Beer s Law, it is best to prepare a calibration curve using a series of standards of known concentration. Instrumental readings are plotted as ordinates against concentrations in, say, mg per lOOmL or lOOOmL as abscissae. For the most precise work each calibration curve should cover the dilution range likely to be met with in the actual comparison. 

Let us now focus attention on the common case where all three binaries exhibit positive deviations from Raoult s law, i.e., afj- > 0 for all ij pairs. If Tc for the 1-3 binary is far below room temperature, then that binary is only moderately nonideal and a13 is small. We must now choose a gas which forms a highly nonideal solution with one of the liquid components (say, component 3) while it forms with the other component (component 1) a solution which is only modestly nonideal. In that event,... 

Again students are expected to realise that this does not represent a stand-alone chemical process, and electrons are not found free under usual conditions, and so this process would need to be coupled with one that provides a place for the electron to go. Students may meet this process as part of a simple redox process (say with the reduction of a less reactive metal), or as one component of the analysis of a more complex process using Hess s law to find an enthalpy change by aggregating the enthalpy terms of an indirect route. 

Section 3.3.4 pointed out that cosolvents alter aqueous ionization constants as the dielectric constant of the mixture decreases, acids appear to have higher pKa values and bases appear (to a lesser extent than acids) to have lower values. A lower dielectric constant implies that the force between charged species increases, according to Coulomb s law. The equilibrium reaction in Eq. (3.1) is shifted to the left in a decreased dielectric medium, which is the same as saying that pKa increases. Numerous studies indicate that the dielectric constant in the region of the polar head groups of phospholipids is 32, the same as the value of methanol. [381,446-453] Table 5.2 summarizes many of the results. 

Or, electrons from atoms of one type, say A, transfer to atoms of another type, say B, to form two kinds of ions a positive kind and a negative kind. These, via Coulomb s Law of electrostatic attraction, become bonded (ionic bonding). 

In order to simplify the situation, we assume that our porous sample under investigation covers the bottom of an open straight-walled can and fills it to a height d (Figure 1). Such a sample will exhibit the same areal exhalation rate as a free semi-infinite sample of thickness 2d, as long as the walls and the bottom of the can are impermeable and non-absorbant for radon. A one-dimensional analysis of the diffusion of radon from the sample is perfectly adequate under these conditions. To idealize the conditions a bit further we assume that diffusion is the only transport mechanism of radon out from the sample, and that this diffusive transport is governed by Fick s first law. Fick s law applied to a porous medium says that the areal exhalation rate is proportional to the (radon) concentration gradient in the pores at the sample-air interface... 

In general, during the initial stages of deformation, a material is deformed elastically. That is to say, any change in shape caused by the applied stress is completely reversible, and the specimen will return to its original shape upon release of the applied stress. During elastic deformation, the stress-strain relationship for a specimen is described by Hooke s law ... 

Given the equation 3CE — 203, we definitely cannot say that O2 reacts with itself to form 03. This equation is the overall reaction, and does not give any information about the mechanism of the reaction, i.e. the order in which bonds are broken and formed to create the products from the reactant. It is only telling us that for every 3 moles of O2 that react, 2 moles of 03 are formed. There is no information in the equation as to how that happens. However, using thermodynamic tables and Hess s Law, we find that AHnn = +286 kJ and AArxn = -137.4 J/mol K, so AGrxn is positive at all temperatures and the reaction must be nonspontaneous at all temperatures. 

Transport in flowing groundwater is controlled primarily by the pattern and rate of flow, which are described by Darcy s law. Darcy s law says that groundwater migrates from high hydraulic potential to low, according to,... 

Let us say that this new surface equilibrium temperature of the water is 15.5 °C then the vapor pressure is 0.0174 atm. At the surface of the water, not only does water vapor exist, but so must the original gas mixture components of air, O2 and N2. By Dalton s law the molar concentration of the water vapor is... 

We may rephrase Hess s law, saying The standard enthalpy of an overall reaction is the sum of the standard enthalpies of the individual reactions into which the reaction may be divided. ... 

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