The reference he used to this effect was the Earth's magnetic field direction, which at that time was believed to be invariant.

He fundamentally defined his arbitrary orientation for the cell as being that in which the internal current would run parallel to and in the same direction as a hypothetical magnetizing current loop around the local line of latitude which would induce a magnetic dipole field oriented like the Earth's.

In retrospect the name change was unfortunate, not only because the Greek roots alone do not reveal the anode's function any more, but more importantly because, as we now know, the Earth's magnetic field direction on which the " anode " term is based is subject to reversals whereas the current direction convention on which the " eisode " term was based has no reason to change in the future.

Early ammeters were laboratory instruments which relied on the Earth's magnetic field for operation.

The tangent galvanometer was used to measure currents using this effect, where the restoring force returning the pointer to the zero position was provided by the Earth's magnetic field.

* Purity and convergence, affected by the Earth's magnetic field, must be factory preset ( biased ) for operation in either the northern hemisphere, the southern hemisphere, or the equatorial area.

Gauss ordered a magnetic observatory to be built in the garden of the observatory, and with Weber founded the " Magnetischer Verein " ( magnetic club in German ), which supported measurements of Earth's magnetic field in many regions of the world.

He developed a method of measuring the horizontal intensity of the magnetic field which was in use well into the second half of the 20th century, and worked out the mathematical theory for separating the inner and outer ( magnetospheric ) sources of Earth's magnetic field.

The reference he used to this effect was the Earth's magnetic field direction, which at that time was believed to be invariant.

He fundamentally defined his arbitrary orientation for the cell as being that in which the internal current would run parallel to and in the same direction as a hypothetical magnetizing current loop around the local line of latitude which would induce a magnetic dipole field oriented like the Earth's.

In retrospect the name change was unfortunate, not only because the Greek roots alone do not reveal the cathode's function any more, but more importantly because, as we now know, the Earth's magnetic field direction on which the " cathode " term is based is subject to reversals whereas the current direction convention on which the " exode " term was based has no reason to change in the future.

The manner in which Xavier's powers function indicates that his telepathy is physical in some way, as it can be enhanced by physical means ( for example, Cerebro ) and can be disrupted by physical means ( for example, Magneto's alteration of the Earth's magnetic field ).

The Earth's magnetic field, approximated as a magnetic dipole.

* Dipole model of the Earth's magnetic field

Later, Enrico befriended another scientifically inclined student named Enrico Persico, and the two worked together on scientific projects such as building gyroscopes and measuring the Earth's magnetic field.

* 0. 31 – 0. 58 gauss – the Earth's magnetic field at its surface

* 25 gauss – the Earth's magnetic field in its core

The Earth's magnetic field lines are horizontal at the magnetic equator.

* The experiment of Wilhelm Röntgen ( 1888 ), to find whether a charged condenser produces magnetic forces due to Earth's motion.

It reduces the Earth's magnetic field inside by about 1500 times.

This made these instruments usable only when aligned with the Earth's field.

Xavier's telepathy once covered the entire world but Magneto altered the Earth's electromagnetic field to restrict Xavier's telepathic range.

A relatively weak gravitational field, such as the Earth's or the sun's, is represented by a metric that is approximately, but not exactly, Euclidean.

Explorer satellites have made important discoveries: Earth's magnetosphere and the shape of its gravity field ; the solar wind ; properties of micrometeoroids raining down on the Earth ; much about ultraviolet, cosmic, and X-rays from the solar system and universe beyond ; ionospheric physics ; Solar plasma ; solar energetic particles ; and atmospheric physics.

Gravitational time dilation in the Earth's gravitational field has been measured numerous times using atomic clocks, while ongoing validation is provided as a side effect of the operation of the Global Positioning System ( GPS ).

The shape of the Earth is to a large extent the result of its rotation, which causes its equatorial bulge, and the competition of geological processes such as the collision of plates and of volcanism, resisted by the Earth's gravity field.

For this reason, the study of the Earth's gravity field is called physical geodesy by some.

At first, oxygen would quickly combine with other elements in Earth's crust, primarily iron, as it was produced.

This is simply because electrons ( ejected from the air by gamma rays ) are stopped quickly in normal air for bursts below roughly 10 km ( about 6 miles ), so they do not get a chance to be significantly deflected by the Earth's magnetic field ( the deflection causes the powerful EMP seen in high altitude bursts ), thus the limited use of smaller burst altitudes for widespread EMP.

It is a common mineral in the Earth's subsurface but weathers quickly on the surface.

Soval also explained that, since Earth recovered from World War III far more quickly than Vulcan did from its equivalent ( in " The Forge " and its sequel episodes, it is said that Vulcans took almost a thousand years to rebuild their society after their last catastrophic war ), it alarmed many Vulcans, who were confused as to how to deal with a rapidly growing and emotional society such as Earth's.

The fragments tend to fall apart quickly into dust, sand, and pebbles, and spread out along the orbit of the comet to form a dense meteoroid stream, which subsequently evolves into Earth's path.

The Invid quickly left Earth rather than risk Earth's destruction by deadly weapons the Neutron_S missiles which were far more dangerous then man believed.

Meanwhile, the AI Sharon Apple has developed a malevolent consciousness and, during her concert in the Atlantis Dome inside Earth's Macross City, quickly takes over both the Ghost X-9 and the SDF-1 Macross Fortress and hypnotizes her audience and the Macross ' staff.

The sodium and potassium carbonate minerals of the lavas formed by Ol Doinyo Lengai are unstable at the Earth's surface and susceptible to rapid weathering, quickly turning from black to grey in color.

The rocks of the peridotite family are uncommon at the surface and are highly unstable, because olivine reacts quickly with water at typical temperatures of the upper crust and at the Earth's surface.

Freeman quickly learns that Earth has been conquered and occupied by the trans-dimensional Combine empire, with a military force powerful enough to have subdued the entirety of Earth's nations within a period of 7 hours.

Already famous for his role in the Black Mesa Incident, Gordon quickly develops a legendary reputation among Earth's surviving human populace, who begin to look up to him and refer to him by such messianic titles as " the One Free Man " or " the Opener of the Way.

Resenting the presence of the Celestials and their monitoring of Earth's progress, the Skyfather figures of Earth ( e. g., Odin, Zeus, and Vishnu ) attempted to stop the Third Host, but are quickly outmatched.

Initially wary of the intentions of an alien race who came " quite uninvited ," even skeptical international leaders begin to be persuaded of the aliens ' benevolence when the Kanamits share their advanced technology, quickly putting an end to many of Earth's greatest woes, including hunger ; energy becomes very cheap ; nuclear weapons are rendered harmless.

Earthquake advance warning is possible by detecting the non-destructive primary waves that travel more quickly through the Earth's crust than do the destructive secondary and Rayleigh waves, in the same way that lightning flashes reaches our eyes before we hear the thunder during a storm.

While the contribution to the Earth's gravitational field from this quadrupole is extremely important for artificial satellites close to Earth, it is less important for the Moon, because the term falls quickly.

The sodium and potassium carbonate minerals of the lavas formed by Ol Doinyo Lengai are unstable at the Earth's surface and susceptible to rapid weathering, the minerals are anhydrous and when they come into contact with the moisture of the atmosphere, they begin to react extremely quickly.