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Page "Electric current" ¶ 62
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flow and positive
Adventurous experiences create psychological and physiological arousal, which can be interpreted as negative ( e. g. fear ) or positive ( e. g. flow ), and which can be detrimental as stated by the Yerkes-Dodson law.
Rather, a system with a negative temperature is hotter than any system with a positive temperature in the sense that if a negative-temperature system and a positive-temperature system come in contact, heat will flow from the negative-to the positive-temperature system.
* In a cathode ray tube, it is the positive terminal where electrons flow out of the device, i. e., where positive electric current flows in.
When a positive voltage is applied to anode of the diode from the circuit, more holes are able to be transferred to the depleted region, and this causes the diode to become conductive, allowing current to flow through the circuit.
They may be positive ( to the flow from the surroundings ) or negative ( to the surroundings from the flow ) depending on the problem.
When used by academics, an arbitrage is a transaction that involves no negative cash flow at any probabilistic or temporal state and a positive cash flow in at least one state ; in simple terms, it is the possibility of a risk-free profit at zero cost.
To provide a definition of current that is independent of the type of charge carriers flowing, conventional current is defined to flow in the same direction as positive charges.
In still others, the current is entirely due to positive charge flow.
In a semiconductor it is sometimes useful to think of the current as due to the flow of positive " holes " ( the mobile positive charge carriers that are places where the semiconductor crystal is missing a valence electron ).
Since current can be the flow of either positive or negative charges, or both, a convention for the direction of current which is independent of the type of charge carriers is needed.
The direction of conventional current is defined arbitrarily to be the direction of the flow of positive charges.
* In vacuum tubes ( including cathode ray tubes ) it is the negative terminal where electrons flow in from the wiring and through the tube's near vacuum, constituting a positive current flowing out of the device.
The cathode supplies electrons to the positively charged cations which flow to it from the electrolyte ( even if the cell is galvanic, i. e., when the cathode is positive and therefore would be expected to repel the positively charged cations ; this is due to electrode potential relative to the electrolyte solution being different for the anode and cathode metal / electrolyte systems in a galvanic cell ).
This sets up conditions for the same type of positive feedback — heat from current flow causes temperature to rise, which increases charge carriers, lowering resistance, and causing more current to flow.
By historical convention, a positive current is defined as having the same direction of flow as any positive charge it contains, or to flow from the most positive part of a circuit to the most negative part.

flow and charges
Rather than a definition in terms of the force between two current-carrying wires, it has been proposed to define the ampere in terms of the rate of flow of elementary charges.
The proposed change would define 1 A as being the current in the direction of flow of a particular number of elementary charges per second.
Typically, electric charges in solids flow slowly.
An electrical insulator is a material whose internal electric charges do not flow freely, and which therefore does not conduct an electric current, under the influence of an electric field.
The " Home charges ", payments transferred from India for administrative costs, were a lasting source of nationalist grievance, though the flow declined in relative importance over the decades to independence in 1947.
When a dielectric is placed in an electric field, electric charges do not flow through the material as they do in a conductor, but only slightly shift from their average equilibrium positions causing dielectric polarization.
Shot noise in electronic circuits consists of random fluctuations of the electric current in a DC current which originate due to fact that current actually consists of a flow of discrete charges ( electrons ).
The red arrows stand for the flow of charges, fluid particles, subatomic particles, photons, etc.
Without the ions from the electrolyte, the charges around the electrode would slow down continued electron flow ; diffusion of H < sup >+</ sup > and OH < sup >−</ sup > through water to the other electrode takes longer than movement of the much more prevalent salt ions.
By design, most of the BJT collector current is due to the flow of charges injected from a high-concentration emitter into the base where there are minority carriers that diffuse toward the collector, and so BJTs are classified as minority-carrier devices.
During discharge, the angular momentum contained in the energy flow is depleted as it is transferred to the charges of the discharge current crossing the magnetic field.
The Biot – Savart law is used to compute the resultant magnetic field B at position r generated by a steady current I ( for example due to a wire ): a continual flow of charges which is constant in time and the charge neither accumulates nor depletes at any point.
Even though charges cannot flow freely in a dielectric, the charges in molecules can move a little under the influence of an electric field.
This opens the ion channel, allowing positively-charged sodium to flow through, reversing the charges momentarily.
Higher current drive increases speed since I = C * dV / dt ; more simply, current is rate of flow of charge, so increased current charges the capacitance faster, and the voltage across a capacitor is equal to the charge on it times the capacitance.
The eddy currents meet resistance as charges flow through the metal, thus dissipating energy as heat, and this acts to slow the wheels down.
A p – n junction diode allows electric charges to flow in one direction, but not in the opposite direction ; negative charges ( electrons ) can easily flow through the junction from n to p but not from p to n, and the reverse is true for holes.

flow and gives
This gives a wide flare to the pecs, causing them to flow dramatically upward into deltoids and dramatically downward into the serratus and Aj.
Electricity gives a wide variety of well-known effects, such as lightning, static electricity, electromagnetic induction and the flow of electrical current.
Uniform flow plus vortex flow ( circulation ) gives the total flow below.
Implementing the rendering equation gives true photorealism, as the equation describes every physical effect of light flow.
In the series finale, " All Good Things ...", Q gives Picard a " helping hand " in saving humanity by helping him figure out what is causing " anti-time " to flow into the universe which will invariably stop humanity from ever being born.
The elimination of reciprocating mass and the elimination of the most highly stressed and failure prone parts of piston engines gives the Wankel engine high reliability, a smoother flow of power, and a high power-to-weight ratio.
A quantum Hall state gives rise to quantized Hall voltage measured in the direction perpendicular to the current flow.
Tolkien has managed to incorporate into the imagery elements of plot ( the horn that was blowing ), his consistent thematic imagery of West and shadow and imagery of the constant seasonal and linear flow of irretrievable time that gives The Lord of the Rings an authentically Anglo-Saxon note.
Adjustment of the nozzle pattern, flow rate, temperature, and etchant composition gives predictable control of etching rates and high production rates.
The advantage of such tools is that it gives the presenter the ability to show his ideas and flow of thoughts rather than simply explain them, which may be more confusing when delivered via simple text instructions.
The high degree of branching with long chains gives molten LDPE unique and desirable flow properties.
When used on SCL, this is called " clock stretching " and gives slaves a flow control mechanism.
Intuitively, it states that the sum of all sources minus the sum of all sinks gives the net flow out of a region.
Compounded by the very steep slope of Nyiragongo gives the lava the ability to flow at up to about 100 km / h ( 62 mph ).
Essentially apolitical, the Guild is primarily concerned with the flow of commerce and preservation of the economy that supports them ; though their ability to dictate the terms of and fees for all transport gives them influence in the political arena, they do not pursue political goals beyond their economic ones.
This configuration gives evidence that for most of its life the Great Belt hosted an outward, downhill flow.
Considering the particular case of fluid dynamics, the difference between the stream function values at any two points gives the volumetric flow rate ( or volumetric flux ) through a line connecting the two points.
The volume divided by the time gives the flow rate.
As the disk nutates, it gives direct indication of the volume of the liquid that has passed through the meter as volumetric flow is indicated by a gearing and register arrangement, which is connected to the disk.
An orifice plate is a plate with a hole through it, placed in the flow ; it constricts the flow, and measuring the pressure differential across the constriction gives the flow rate.

1.316 seconds.