VOLTAGE BREAKDOWN IN IONIZED AIR AT FREQUENCIES FROM ZERO TO 10,000 MEGACYCLES

During the summer of 1957, The Martin Company, Denver Division, expressed a need for experimental data which would enable more exact design of surface- mounted antennas on missiles which would avoid corona and voltage breakdown in the higher atmosphere. Inasmuch as some experimental data were then avail* able, a request was also made for a literature search on voltage breakdown is air as a function of pressure, frequency, pulse length, electrode spacing, and degree of ionization. Contract No. DEN 57-5652, under Prime Contract AF 04 (645) 56, was initiated with the Purdue Research Foundation in January, 1958, to obtain (l) a literature search and (2) experimental data covering a range of the parameters listed above. The literature search was delivered to The Martin Company on November 25, 1958. The experimental data are the subject of this report

Testing theoretical models of magnetic damping using an air track

Magnetic braking is a long-established application of Lenz's law. A rigorous analysis of the laws governing this problem involves solving Maxwell's equations in a time-dependent situation. Approximate models have been developed to describe different experiences related to this phenomenon. In this paper we present a new method for the analysis of the magnetic braking using a magnet fixed to the glider of an air track. The forces acting on the glider, a result of the eddy currents, can be easily observed and measured. As a consequence of the air track inclination, the glider accelerates at the beginning, although it asymptotically tends towards a uniform rectilinear movement characterized by a terminal speed. This speed depends on the interaction between the magnetic field and the conductivity properties of the air track. Compared with previous related approaches, in our experimental setup the magnet fixed to the glider produces a magnetic braking force which acts continuously, rather than over a short period of time. The experimental results satisfactorily concur with the theoretical models adapted to this configuration.Comment: 15 pages, 5 figure

On the propagation of Voigt waves in energetically active materials

If a dissipative anisotropic dielectric material, characterized by the permittivity matrix $\underline{\underline{\epsilon}}$, supports Voigt-wave propagation, then so too does the analogous active material characterized by the permittivity matrix $\underline{\underline{{\tilde{\epsilon}}}}$, where $\underline{\underline{{\tilde{\epsilon}}}}$ is the hermitian conjugate of $\underline{\underline{\epsilon}}$. Consequently, a dissipative material that supports Voigt-wave propagation can give rise to a material that supports the propagation of Voigt waves with attendant linear gain in amplitude with propagation distance, by infiltration with an active dye

Electronic circuits and design

xv, 423 p.; 23 cm

Electronic Circuit Analysis and Design

xvi, 423 hlm.; 23 c