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Elettromagnetismo

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La Terra gira a 1600 km orari: un laser ci darà la misura esatta. ROMA - Quando un fascio di luce si accende dentro a una montagna, può accadere che Einstein incontri la scienza dei terremoti.

La Terra gira a 1600 km orari: un laser ci darà la misura esatta

Questo gioco delle (strane) coppie ha luogo nei Laboratori del Gran Sasso dell'Istituto nazionale di fisica nucleare (Infn). È un esperimento dal nome piccante: Gingerino (Gyroscopes in General Relativity). È nato per misurare una delle implicazioni della teoria della Relatività non ancora del tutto comprovata, ma ha scoperto di essere utile anche a chi studia la rotazione e le deformazioni della Terra. Gingerino è uno strumento montato a 1.400 metri di profondità per misurare gli effetti della rotazione terrestre. A phone that charges in seconds? Scientists bring it closer to reality. A team of UCF scientists has developed a new process for creating flexible supercapacitors that can store more energy and be recharged more than 30,000 times without degrading.

A phone that charges in seconds? Scientists bring it closer to reality

The novel method from the University of Central Florida's NanoScience Technology Center could eventually revolutionize technology as varied as mobile phones and electric vehicles. "If they were to replace the batteries with these supercapacitors, you could charge your mobile phone in a few seconds and you wouldn't need to charge it again for over a week," said Nitin Choudhary, a postdoctoral associate who conducted much of the research published recently in the academic journal ACS Nano.

Anyone with a smartphone knows the problem: After 18 months or so, it holds a charge for less and less time as the battery begins to degrade. Scientists have been studying the use of nanomaterials to improve supercapacitors that could enhance or even replace batteries in electronic devices. Sole 'sbuffa' di nuovo, rischio di una tempesta magnetica - A primer on particle accelerators. Research in high-energy physics takes many forms.

A primer on particle accelerators

But most experiments in the field rely on accelerators that create and speed up particles on demand. What follows is a primer on three different types of particle accelerators: synchrotrons, cyclotrons and linear accelerators, called linacs. Illustration by Sandbox Studio, Chicago with Jill Preston. Nothing to mach > Holloman Air Force Base > Article Display. “Ten, nine, eight, seven, six…” A steady voice reads through a crackling radio atop a roughly hewn 2x4 wooden shelf, adding lumber to the smells of coffee and aftershave inside the enclosed trailer.

nothing to mach > Holloman Air Force Base > Article Display

Red LED numbers attached to the radio flash their faint light as they drop toward zero. “…five, four, three…” Rolling chairs anxiously scrape across the trailer floor as the four men position themselves to better see through a dirty window. They train their eyes toward the track a quarter of a mile away. “…two, one…” Half a year of long days in the New Mexico sun brought them to this moment. “…fire.” Everyone in the trailer holds their breath in anticipation for t… A violent explosion from the track rocks the trailer and everyone inside. A firestorm erupts behind a 2,000-pound, magnetically-levitated sled as it races across the nearly frictionless track.

The 846th Test Squadron broke their own world record for speed on a magnetically-levitated sled system at Holloman AFB on March 4. L’Uomo fulmine che resiste alle scariche elettriche. Solar Dynamics Observatory. Solar Irradiance The primary source of energy to the Earth is radiant energy from the Sun.

Solar Dynamics Observatory

This radiant energy is measured and reported as the solar irradiance. When all of the radiation is measured it is called the Total Solar Irradiance (TSI); when measured as a function of wavelength it is the spectral irradiance. Light of different wavelengths reaches different parts of the Earth's atmosphere. Visible light and infrared radiation reach the surface, warming the surface to livable conditions. Each part of the solar irradiance changes over the 11-year solar cycle, becoming brighter than average at solar maximum and dimmer at solar minimum. To understand the mechanisms that cause EUV irradiance variations, two sets of measurements are required. Our Sun, a Weather Maker Energy leaves the Sun as photons, energetic particles, and magnetic fields.

Offering A New View of the Solar Wind. An artist's rendition of NASA's Interface Region Imaging Spectrograph, or IRIS, mission in space.

Offering A New View of the Solar Wind

Credits: NASA/Goddard Space Flight Center NASA's newest sun-watcher, the Interface Region Imaging Spectrograph, launched in 2013 with a specific goal: track how energy and heat coursed through a little understood region of the sun called the interface region. Sandwiched between the solar surface and its outer atmosphere, the corona, the interface region is where the cooler temperatures of the sun's surface transition to the hotter temperatures above.

Moreover, all the energy to power the sun's output -- including eruptions such as solar flares and the sun's constant outflow of particles called the solar wind -- must make its way through this region. Five papers based on IRIS data will highlight different aspects of the energy’s journey from the sun’s surface through its atmosphere in the Oct. 17, 2014, issue of Science magazine. Solar Heat Bombs Credits: NASA/IRIS/Peter. La pila più potente è trenta volte più piccola. La microbatteria sviluppata all’Università dell’Illinois (da engineering.illinois.edu) È tanto piccola quanto potente la batteria sviluppata all’Illinois University di Urbana-Champaign.

La pila più potente è trenta volte più piccola

Di pochi millimetri, potrebbe alimentare un cellulare o riavviare un’auto in panne. E ricaricarsi in un batter d’occhio. Per realizzarla, i ricercatori hanno ridisegnato la microstruttura interna, inserendo un catodo a ricarica rapida e sviluppando un nuovo processo d’interazione con l’anodo corrispondente. Le batterie a carica superveloce.

Un gruppo di ricercatori della Nanyang Technological University (NTU) di Singapore ha annunciato di avere realizzato un nuovo tipo di batteria che può essere ricaricata fino al 70 per cento in appena due minuti.

Le batterie a carica superveloce

Il sistema permette inoltre di preservare meglio i componenti della batteria, permettendo di farle sopportare fino a 20 anni di ricariche senza perdite significative della sua capacità. L’annuncio sta circolando molto perché potrebbe costituire una soluzione all’annoso problema della scarsa durata della carica di diversi dispositivi, come gli smartphone o le auto elettriche.