XXXII.—Observations of the Earth-air Electric Current and the Atmospheric Potential Gradient at Edinburgh

1910 ◽  
Vol 30 ◽  
pp. 460-465 ◽  
Author(s):  
G. A. Carse ◽  
D. MacOwan
Keyword(s):  
Electric Current ◽  
Potential Gradient ◽  
Ground Level ◽  
Dissipation Factor ◽  
Test Plate ◽  
Gold Leaf ◽  
The Earth ◽  
Zero Potential

The portable gold-leaf electrometer designed by C. T. R. Wilson gives a means of measuring the charge upon and current through a conductor exposed to the earth's field and maintained at zero potential. Further, Wilson has shown (1) that the dissipation factor (the ratio of current per minute to the corresponding charge) is approximately the same for a surface of turf and the metal test-plate; and (2) how to deduce the corresponding charge and current per square centimetre on the neighbouring ground-level. Wilson's measurements were made chiefly in a country atmosphere (near Peebles), and we have made observations with a similar instrument in town air, in and near Edinburgh, to find out whether the dissipation factor is notably affected by the purity of the atmosphere as regards smoke, etc.

scholarly journals On the measurement of the atmospheric electric potential gradient and the earth-air current

1908 ◽  
Vol 80 (542) ◽  
pp. 537-547 ◽  
Keyword(s):  
Experimental Error ◽  
Unit Area ◽  
Potential Gradient ◽  
Dissipation Factor ◽  
Ordinary Condition ◽  
Electrical Field ◽  
Test Plate ◽  
The Earth ◽  
Zero Potential ◽  
Atmospheric Electric Potential Gradient

In previous papers I have described a method of measuring the charge upon and current through a conductor exposed to the earth’s electrical field and maintained at zero potential. The present paper contains an account of a series of such measurements, taken primarily with the object of testing the method, and, in particular, of gaining some evidence as to whether it is legitimate to deduce from the “dissipation factor,” found for the exposed “test-plate” of the apparatus, the current from the atmosphere into each square centimetre of the ground when the potential gradient is known. With the object of gaining information on this question, alternate measurements were made with the apparatus in its ordinary condition, and with its test-plate covered with turf. It was thought that if the ratio of the current to the charge on the exposed surface were found to be the same in the two cases, it might with some confidence be assumed that the same ratio would hold for the current and charge per unit area of the ground. As will be seen later, the ratio of the current to the charge remained within the limits of experimental error unaltered when the test-plate was covered with turf.

scholarly journals III. Investigations on lighting discharges and on the electric field of thunderstorms

1921 ◽  
Vol 221 (582-593) ◽  
pp. 73-115 ◽  
Keyword(s):  
Electric Field ◽  
Potential Gradient ◽  
Ground Level ◽  
Electric Discharges ◽  
Test Plate ◽  
Before And After ◽  
Flat Portion ◽  
The Difference ◽  
Zero Potential ◽  
Absolute Measurements

The method and apparatus used in the measurements are substantially those described in a paper "On Some Determinations of the Sign and Magnitude of Electric Discharges in Lightning Flashes." The induced charge on an exposed earthed conductor (test-plate or sphere) is used as a measure of the electric field. The testplate virtually forms part of a flat portion of the earth’s surface, and the vertical electric force or potential gradient at ground level is equal (in electrostatic measure) to 4 π Q/A, where Q is the charge on its exposed surface and A is its area. The charge Q on the earth-connected sphere of radius R, when exposed at a height h , great compared with R, is a measure of the potential at that height; the zero potential of the sphere being the resultant of the undisturbed atmospheric potential V at the height h and of the potential Q/R due to the charge on the sphere, so that Q/R = - V. The earthed conductors can be shielded from the earth’s field: the test-plate by means of an earth-connected cover, the sphere by lowering it into a conducting case resting on the ground. The quantity of electricity which flows to earth through the connecting wire on exposing or shielding the test-plate or sphere, is measured by a special type of capillary electrometer in which the readings indicate the total quantity of electricity which has traversed the instrument ; the sign and magnitude of the charge on the exposed conductor, and thus of the potential gradient, at the beginning and end of an exposure are thus determined. The sign and magnitude of sudden changes of potential gradient which occur while the conductor is exposed are indicated by the direction and magnitude of the resulting displacements of the electrometer meniscus. The total flow of electricity between the atmosphere and the test-plate or sphere during an exposure is also measured —being given by the difference between the electrometer readings before and after the exposure. The principal improvement introduced has been the provision of apparatus for giving a photographic trace of the electrometer readings; rapid changes in the field occupying less than one-tenth of a second are in this way recorded. In the observations described in the previous paper the sphere was supported in a manner which did not admit of absolute measurements being made, as the charge measured included that on the upper part of the support as well as that on the sphere itself; in these earlier measurements therefore the sphere was standardised by comparison with the test-plate. The method of supporting the sphere is now such that the charge on the sphere alone is measured, while the disturbing effect of the earthed supporting rod is small, and thus the potential at the level of the earthconnected sphere can be calculated from the charge upon it. The new method of mounting the sphere is shown in fig. 1.

IN-FLIGHT EXPOSURE TO COSMIC RADIATION ALONG SOME COMMERCIAL AIRLINE ROUTES TO AND FROM NIGERIA

2017 ◽  
Vol 15 (1) ◽  
pp. 57-69
Author(s):  
O O ALATISE ◽  
A A ADEPOJU
Keyword(s):  
Effective Dose ◽  
Radiation Protection ◽  
Cosmic Radiation ◽  
Ground Level ◽  
Radiation Doses ◽  
Human Beings ◽  
The Earth ◽  
Commercial Airline ◽  
Additional Level ◽  
Airline Crews

The study of “external” radiation called cosmic radiation that strikes the earth from anywhere beyond the atmosphere is of great importance in radiation protection. All human beings are exposed to an uncontrollable amount of cosmic radiation on the ground level. Those who travel in space, airline crews and frequent flyers are exposed to additional level of cosmic radiation during their trip but unfor-tunately many of them are not aware of this. This workcalculates the exposure of aircrews and fre-quent flyers to cosmic radiation during travel along some air routes to and from Nigeria. The effective dose was computed using a dedicated software CARI 6M, developed by US FAA.The study focuses on the significance of the in-flight exposure, assessment and estimation of in-flight exposure using the dedicated software and some ways of controlling the exposures so that airline crews and frequent flyers are not exposed to fatal levels of radiation.It was observed that the cosmic radiation doses re-ceived by passengers and crew members on board on flights from Lagos Nigeria to countries in Amer-ica were more than what they received en-route countries in Asia.

ELECTRIC EARTH TRANSIENTS IN GEOPHYSICAL PROSPECTING

Geophysics ◽  
1936 ◽  
Vol 1 (2) ◽  
pp. 271-277 ◽  
Author(s):  
Louis Statham
Keyword(s):  
Electric Current ◽  
Salt Dome ◽  
Geophysical Prospecting ◽  
The Earth ◽  
Electrical Methods ◽  
The Times

A suddenly applied electric current is passed through the earth by means of spaced electrodes. The form of the potential transient as it appears outside the current electrodes is studied. The potential transient is extremely rapid and refined methods of recording are necessary. Means for measuring the relative times of the transient potentials received from different points are discussed. A survey taken over a known deep salt dome is shown; anomalous times of the transients are found to exist over the dome. No correlation is seen between the times of the transients and the resistivity as found by ordinary electrical methods.

scholarly journals Short- and Medium-Term Induced Ionization in the Earth Atmosphere by Galactic and Solar Cosmic Rays

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Alexander Mishev
Keyword(s):  
Cosmic Rays ◽  
Cosmic Ray ◽  
Ground Level ◽  
Galactic Cosmic Rays ◽  
Earth Atmosphere ◽  
Medium Term ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
The Earth ◽  
Ionization Effect

The galactic cosmic rays are the main source of ionization in the troposphere of the Earth. Solar energetic particles of MeV energies cause an excess of ionization in the atmosphere, specifically over polar caps. The ionization effect during the major ground level enhancement 69 on January 20, 2005 is studied at various time scales. The estimation of ion rate is based on a recent numerical model for cosmic-ray-induced ionization. The ionization effect in the Earth atmosphere is obtained on the basis of solar proton energy spectra, reconstructed from GOES 11 measurements and subsequent full Monte Carlo simulation of cosmic-ray-induced atmospheric cascade. The evolution of atmospheric cascade is performed with CORSIKA 6.990 code using FLUKA 2011 and QGSJET II hadron interaction models. The atmospheric ion rate is explicitly obtained for various latitudes, namely, 40°N, 60°N and 80°N. The time evolution of obtained ion rates is presented. The short- and medium-term ionization effect is compared with the average effect due to galactic cosmic rays. It is demonstrated that ionization effect is significant only in subpolar and polar atmosphere during the major ground level enhancement of January 20, 2005. It is negative in troposphere at midlatitude, because of the accompanying Forbush effect.

Things are Not Always What They Seem! Joule Burns in Electrocution—A Report of Four Cases

1987 ◽  
Vol 27 (1) ◽  
pp. 63-67 ◽  
Author(s):  
W. O. Odesanmi
Keyword(s):  
Electric Current ◽  
The Body ◽  
Gold Leaf ◽  
Earth Fault ◽  
Electrical Engineers ◽  
Tear Gas ◽  
University Undergraduates ◽  
Electric Burns

The police dispersed a crowd of University undergraduates with tear gas, and four of these students were later found dead around an advertisement pole carrying a plastic encasement displaying the picture of ‘Gold Leaf’ cigarette. It was alleged that the students were killed by the police. Autopsy of the four students revealed electric burns scattered all over the body. These burns were later found to be situated at points where the body had made contact with the advertisement pole. The pole was later examined by a team of electrical engineers and found to have a severe earth fault which on test resulted in a potentiation of 175 volts between the body of the sign post and the immediate surrounding. It was the source of the electric current that caused the death of the students.

The Ground-level Enhancements of 1989 September 29 and October 22

1993 ◽  
Vol 10 (3) ◽  
pp. 211-217 ◽  
Author(s):  
M.L. Duldig ◽  
J.L. Cramp ◽  
J.E. Humble ◽  
J.W. Bieber ◽  
P. Evenson ◽  
...  
Keyword(s):  
Particle Flux ◽  
Temporal Structure ◽  
Cosmic Ray ◽  
Ground Level ◽  
Reverse Direction ◽  
Particle Injection ◽  
The Earth ◽  
Particle Propagation ◽  
Multiple Particle ◽  
Ground Level Enhancements

Abstract During the solar maximum of 1989–91 an unprecedented sequence of 13 cosmic ray ground-level enhancements (GLEs) was observed by the world-wide neutron monitor network. Of particular interest were two GLEs observed by the Australian network. The 1989 September 29 event was the largest GLE in the space era while the October 22 GLE included an highly anisotropic precursor peak.Analysis of both these GLEs, taking into account disturbed geomagnetic conditions, shows that the particle arrivals at the earth were unusual. The September 29 GLE had significant particle propagation in the reverse direction and as the particle flux decreased following the peak the spectrum also softened. In contrast, the 1989 October 22 precursor exhibited extreme anisotropy while the particles involved in the main GLE showed a complex temporal structure possibly indicating multiple particle injection at the solar acceleration region.

scholarly journals On line-integrals of the diurnal magnetic variations

1928 ◽  
Vol 119 (782) ◽  
pp. 182-196 ◽  
Keyword(s):  
Electric Current ◽  
Potential Gradient ◽  
Electromagnetic Theory ◽  
Magnetic Data ◽  
Magnetic Survey ◽  
Electric Currents ◽  
Direct Measurements ◽  
On Line ◽  
Current Densities ◽  
Current Flows

1. According to electromagnetic theory, the line-integral ∫ H . ds of the magnetic force H taken round any closed curve is equal to 4πI, where I is the electric current threading the curve, H and I being measured in c.g.s. units. Such line-integrals have been calculated by Gauss and many later investigators for various curves on the earth’s surface, in order to determine whether any electric current flows upwards or downwards across the surface. Modern computations for large areas lead in general to values of ∫ H . ds differing from zero by amounts that correspond to current-densities of the order 3·10 -2 ampere/km. 2 . The magnetic field of such currents would account for 2 or 3 per cent, of the earth’s surface field. These results are inconsistent with the direct measurements of the atmospheric electric potential gradient and the ionisation of the air, which indicate a verticalcurrent-density of the order 3·10 -6 amp./km. 2 . If the magnetic estimates are reliable, the discrepancy indicates either that atmospheric electric currents exist which escape measurement, though they are 10,000 times as great as those which are measured, or that the relation ∫ H . ds = 4πI, which is one of the foundations of electromagnetic theory, is not strictly correct. These alternatives are so remarkable that the magnetic evidence must be above suspicion if it is to gain credence. Dr. L. A. Bauer holds that the results got from independent sets of data, for different epochs, and the mutual accordance of the results from neighbouring areas, justify the acceptance of the non-zero line-integrals, and that to explain them away it is necessary to assume quite unlikely systematic errors in the magnetic data. Other investigators show less conviction: for example, Sir Frank Dyson and H. Furner conclude that “though there is some evidence for Prof. Bauer’s results, the existence of vertical electric currents is not indicated with any great certainty.” But though the magnetic evidence may not be conclusive, it cannot be lightly dismissed, and in view of the importance of the question Sir Arthur Schuster has recently urged the desirability of a detailed magnetic survey of a small area as the best means of obtaining a definite conclusion.

scholarly journals THE MAGNETIC PROPERTIES MEASUREMENT OF COIL FOR GRAVITATIONAL ACCELERATION DETERMINATION

2020 ◽  
Vol 5 (2) ◽  
pp. 119-128
Author(s):  
Cherly Salawane ◽  
Supriyadi Supriyadi ◽  
Ronaldo Talapessy ◽  
Mirtha Yunitha Sari Risakotta
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Field Strength ◽  
Electric Current ◽  
Graphical Method ◽  
Current Strength ◽  
Gravitational Acceleration ◽  
The Earth ◽  
The Magnetic Field ◽  
A Current

The value of the gravitational acceleration of the earth above the earth’s surface depends on the position of the latitude and longitude of the earth’s surface, in other words, because the shape of the earth’s surface is not round like a ball. The magnitude of gravity is not the same everywhere on the surface of the earth. The purpose of this study is to analyze the value of the earth’s gravitational acceleration in a laboratory using a current balance with a graphical method. Fluctuations in the value of the magnetic field strength (B) and the value of the electric current strength (i) on the current balance cause the value of laboratory gravitational acceleration (glab) to vary in the transfer of electric charge (q) according to coil type. The magnitude of the earth’s gravitational acceleration value obtained in a laboratory with a current balance for each type of coil is as follows: SF-37 glab-nr=9.89 m/s2, SF-38 glab-nr=9.90 m/s2, SF-39 glab-nr=9.76 m/s2, SF-40 glab-nr=9.95 m/s2, SF-41 glab-nr=9.75 m/s2 dan SF-42 glab-nr=9.93 m/s2. The results obtained indicate that the value of the earth’s gravitational acceleration in a laboratory close to the literature value is the value of the glab-nr in the SF-37 coil type of 9.89 m/s2.

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