Shot Effect definition of Shot Effect in the Free Online Encyclopedia.

shot effect [′shät i‚fekt]

(electronics)

Shot Effect

small random deviations of the anode current in vacuum electrical and semiconductor devices from its mean value; caused by nonuniformity of electron emission from the cathode or by nonuniform diffusion of charge carriers in semiconductors. The effect was predicted theoretically by the German scientist W. Schottky in 1918.

Upon heating of the cathode of a vacuum electrical device the average speed of thermal motion of the conduction electrons is increased. Some of the electrons—those having sufficient kinetic energy—“escape” from the cathode. How-ever, before leaving the cathode, the electron undergoes a very large number of collisions with atoms and other electrons inside the cathode. As a result, the magnitude and direction of the velocity of each electron at the moment of departure from the cathode may be different. Therefore, the departure of individual electrons appears to occur altogether at random, independent of the departure of other electrons. As a result, the number of electrons emitted by the cathode during identical short time periods differs, and in turn the emission current experiences random deviations (fluctuations) from its mean value. The magnitude of the fluctuations of the anode current depends mainly on the conditions under which the device is operating. In electron tubes, if all emitted electrons strike the anode, the emission fluctuations are precisely repeated in the anode current. However, if not all of the electrons strike the anode, then around the cathode a negatively charged cloud is formed that acts as a “damper” and smooths out the shot fluctuations of the anode current.

The shot effect is not characteristic only of thermionic emission; it accompanies any process associated with the formation of flows of charged or neutral particles—for example, the passage of electric current through semiconductors, photoelectric emission, secondary electron emission, and the formation of molecular beams.

The term “shot effect” (and also “shot noise”) originated because, as a result of this phenomenon, an acoustic noise resembling the noise of falling pellets occurs in a loudspeaker connected to the output of an amplifier or radio.

REFERENCES

Vlasov, V. F. Elektronnye i ionnye pribory, 3rd ed. Moscow, 1960. Pages 305-17.
Van der Ziel, A. Fluktuatsii v radiotekhnike i fizike. Moscow-Leningrad, 1958. Pages 63-209. (Translated from English.)
Bonch-Bruevich, A. M. Radioelektronika v eksperimental’noi fizike. Moscow, 1966. Pages 193-200.

I. T. TROFIMENKO

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No references found	The first problem is that a stun gun shot effects the attacker in a time gap of three seconds or sometime in five seconds. Stun Guns and Its Limitations by michael russell / Business community The number of goals per regular season game in junior and height are positively related to the number of points per regular season game in the NHL, whereas shot and draft rank are negatively related to the dependent variable, The shot effect indicates that left shooting right wingers (M = 0. Predictors of performance in the National Hockey League by Voyer, Daniel; Wright, Edward F. / Journal of Sport Behavior	Shoshone National Forest Shoshone project Shoshone River Shoshonean Languages Shoshoni shoshonite Shosse Shostakovich Shostakovich, Dmitri Shostakovich, Dmitrii Shostakovich, Dmitrii Dmitrievich Shostakovich, Dmitry Shostakovskii, Mikhail Shostakovskii, Mikhail Fedorovich Shostka Shot shot bit shot blasting shot boring shot break shot capacity shot copper shot depth shot drill Shot Drilling Shot Effect shot elevation Shot Exploder shot feed shot group shot hole shot mill Shot Noise shot pattern shot peening shot point shot put shot rock shot tongs shot tower Shot Tower Historical State Park Shot, Hunting shot-firing cable shot-firing circuit shot-firing curtain shot-sawn finish Shota Grigorevich Nishnianidze Shota Nishnianidze Shota Rustaveli shotblasting shotcrete	shot a line shot a line shot a line Shot across the bow Shot Across the Bow Productions shot at Shot belt shot bit shot blasting Shot Blocked shot boring shot break Shot Brot Shot bush shot capacity Shot cartridge shot clock shot copper shot cuffs shot cuffs shot cuffs shot cuffs Shot Dead in Vegas shot depth shot down shot down shot down shot down shot drill Shot Drilling Shot Effect shot elevation Shot Exploder shot feed shot from the hip shot from the hip shot from the hip shot from the hip shot full of holes Shot garland Shot gauge shot glass shot glasses shot group shot hole shot hole shot holes shot holes shot in the arm shot in the arm shot in the arm shot in the arm shot in the dark shot in the dark shot in the dark shot in the dark Shot in the Dark Photography shot in the foot shot in the foot shot in the foot shot in the foot

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The first problem is that a stun gun shot effects the attacker in a time gap of three seconds or sometime in five seconds.

Stun Guns and Its Limitations by michael russell / Business community

The number of goals per regular season game in junior and height are positively related to the number of points per regular season game in the NHL, whereas shot and draft rank are negatively related to the dependent variable, The shot effect indicates that left shooting right wingers (M = 0.

Predictors of performance in the National Hockey League by Voyer, Daniel; Wright, Edward F. / Journal of Sport Behavior