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The innate capacity to increase in number is defined as the maximum rate (mr) of increase obtained by a population of fixed age distribution, in any combination of the physical factors of time, under optimal conditions of space, feeding, and intra-specific influence, excluding inter-specific influence. In this work, the hypothesis is that there is a thermal threshold, this is the base temperature (Tb) for the development of Atherigona Orientalis, and the increase and/or decrease of the population is a function of its survival, fertility, sex ratio, and fecundity, with thresholds influenced by isotherms. These equations determined the number of generations per year of the bioindicator Atherigona Orientalis for isotherms from 21 C to 27 C. Through the number of individuals of the last compartment (females in pre-oviposition), obtained through the simulations, as a function of time, for each isotherm, it was possible to estimate the number of annual generations conditioned to a system without gains or losses. Depending on the temperature, Atherigona Orientalis can present from 4,19 to 8,23 and 4,74 to 8,55 generations per year when obtained through the development equations and simulations, respectively, and the higher the temperature higher the number of generations. [ABSTRACT FROM AUTHOR]

The influence of the air resistance over a body moving over a slant cable was studied using an integrated approach, including modelling, analytical solutions to ordinary differential equations, experimental practice and the estimation of error margins for the experimental data. The proposed setup allows for three different configurations for the moving body, one without coating, with a small transverse section area, and two with coating, with higher transverse section area, and this allows us to experimentally demonstrate not only the dependence of air resistance with the transverse area, but also with the format of the moving body. As a result of our methods, we were able to determine properties such as friction coefficient, air resistance coefficient per mass unit and limiting speed. The proposed experiment involves only low cost materials and can be adapted to be used as an activity in college education. [ABSTRACT FROM AUTHOR]

Searching for solution of a differential equation can be one of the main tasks of a physicist. In this sense, the greater the number of known solution methods, the wider the variety of problems that can be analyzed and understood. Among the differential equations, the non-linear equations are the ones with the greatest resolution complexity and are routinely present in the description of natural phenomena. In this perspective, this work presents an introduction to the Adomian Decomposition Method, which is an analytical method vastly used to address non-linear differential equations. To exemplify the applicability of the Adomian method, some linear and non-linear examples are treated, namely: free fall of a particle under air resistance, simple gravity pendulum and a one-dimensional non-uniform transport wave equation. [ABSTRACT FROM AUTHOR]

We consider the motion of a particle launched obliquely under gravity force and air resistance proportional to velocity. We obtain, via differential calculus, general informations about the trajectory of the particle as increasing and decrease intervals, maximum point, concavity, asymptotic behavior, horizontal reach etc., allowing us tracing the profile of this trajectory without the use of numerical tables and without the need to make approximations. We present a demonstration that, although there is no explicit exact expression for the horizontal reach of the particle, it is always smaller as larger the value of air resistance parameter, which matches the physical situation under consideration. [ABSTRACT FROM AUTHOR]

In 14/10/2012 Felix Baumgartner made his record jump into the atmosphere. A video registered measurements of time, speed, altitude and acceleration during all the motion. These data allowed many considerations about Mechanics and Atmosphere Physics related to the event. Beyond the three worldwide known records that were broken with this jump (initial altitude, extensive of the fall, and the first reaching of a supersonic speed in the jump without a parachute), it is demonstrated in this paper that it has also been broken a record of free fall with acceleration, in accordance with the International Gravity Formula, during a time of more than 20 s and along an extension of about 3 km. It is also developed a model for the speed during the jump without parachute, consistent with the data collected in the video. [ABSTRACT FROM AUTHOR]

Resumo Os tiros de comemoração referem-se aos tiros dados para o alto por ocasião de celebrações festivas. Este é um hábito em países como o Afeganistão, Paquistão e algumas regiões da América Latina. Neste artigo, resolvemos o problema de projéteis com velocidade subsônica atirados para alto, considerando a resistência do ar. Com fins didáticos, traçamos um paralelo entre esse caso e aquele em que a resistência do ar é desprezada. Concluímos que mesmo projéteis de pequeno calibre podem ser letais na queda, apesar da diminuição da velocidade e da energia cinética.