Physics questions

The wavelength is commonly designated by the Greek letter lambda (λ).

Acctually due to recent research, it appeared that abnormalities in gravitational fields astronomers have predicted that there might be a primordial black hole prevailing in the dust errees near the oort cloud. :SCIENCE FREAK

UV radiation was discovered in 1801 when the German physicist Johann Wilhelm Ritter observed that invisible rays just beyond the violet end of the visible spectrum darkened silver chloride-soaked paper more quickly than violet light itself.

Well logs measure different physical properties of the subsurface strata. Resistivity is measured very close to the tool (MFSL), at shallow depth from the tool (LLS) and at deep depths (LLD). If there is a big difference in the resistivities it means that the deeper formation contains hydrocarbons which have very high resistivity.

The speed at which light propagates through transparent materials, such as glass or air, is less than c. However, this "slowing of the light" is only due to the fact of photos being absorbed and re-emitted after a slight delay between atoms. When a photon is emitted, it's speed is always c. In exotic materials like Bose–Einstein condensates near absolute zero, the effective speed of light may be only a few metres per second.

Sprites are large-scale electrical discharges that occur high ( 50–90 km) above cumulonimbus, giving rise to a quite varied range of visual shapes flickering in the night sky. They are usually triggered by the discharges of positive lightning between an underlying thundercloud and the ground. Sprites have been blamed for otherwise unexplained accidents involving high altitude vehicular operations above thunderstorms. Since their 1989 discovery, sprites have been imaged from the ground, from aircraft and from space, and have become the subject of intensive investigations.

The Pinwheel Galaxy ( M101) is a face-on spiral galaxy distanced 21 million light-years away from Earth in the constellation Ursa Major. M101 is a large galaxy, with a diameter of 170,000 light-years. By comparison, the Milky Way has a diameter of 258,000 light years. It has around a trillion stars, twice the number in the Milky Way. It has a disk mass on the order of 100 billion solar masses, along with a small central bulge of about 3 billion solar masses.

By far most of the solar system's mass is in the Sun itself: somewhere between 99.8 and 99.9 percent. The rest is split between the planets and their satellites, and the comets and asteroids and the dust and gas surrounding our star.

Henry Cavendish, british physicist (1731-1810) was the first scientist to calculate mass of the Earth. Greater accuracy has not been achieved for nearly 100 years. He only made a mistake about 1% compared to today's calculations. Cavendish estimated the mass of the Earth to be 6 billion trillion tons. Modern calculations say about 5.9725 billion trillion tons. (5,97219×10^24 kg)

In Building 87 on Microsoft’s Redmond campus, you’ll find an anechoic chamber—a space designed to absorb and isolate sound—built by Eckel Industries and certified by the Guinness Book of World Records as the quietest place on Earth in 2015. The chamber is so effective that the ambient level of noise inside is actually -20.6 decibels. To put that in perspective, the ambient sound level of a person in a very quiet room breathing as a resting rate is around 10 decibels.