What are neutrinos?
Neutrinos are objects produced by the decay of certain subatomic particles.
They have energy but little or no mass, and they travel almost at the speed of light.
Avoirdupois weight is the system we use whenever we measure a grain, dram (27.3 grains), ounce (16 drams), or pound (16 ounces).
Both stalagmites and a stalactites are elongated deposits of minerals at points where slowly dripping water enters a void. Stalagmites build from the bottom of such a cavity; stalactites hang from the ceiling. When the same dripwater source creates both a stalactite and a stalagmite, the two may meet and form a column.
The average body has 14 to 18 square feet of skin.
A quasar is another name for a quasi-stellar object. It looks like a star but emits as much radiation as an entire galaxy, with a volume far smaller than that of our Milky Way galaxy. No one knows what a quasar is; recent evidence suggests it might be a galaxy with a big black hole…
The largest plant in the world is said to be the General Sherman Tree, a giant sequoia in Sequoia National Park, California. The tree is about 272 feet tall and more than 100 feet in circumference. It is about 3,500 years old.
The first to approximate the speed of light roughly was French physicist Armand Fizeau (1819-1896). In 1849 Fizeau obtained a value for the speed of light that was about 5 percent too high. Fizeau’s contemporary Jean Foucault (1819-1868) obtained the first accurate measurement (within 1 percent of the correct speed) in 1862.