Once standard fantasy in the world of science fiction, invisibility cloaks are viable products as of 2014. There are three types of invisibility cloaks. The first uses carbon nanotube, another uses metamaterials, and the third uses optical camouflage technology.Know More
Invisibility cloaks that use carbon nanotubes essentially create a mirage effect to trick the viewer into thinking he is seeing something else. To make this happen, sheets of carbon nanotube are rolled in a cylindrical fashion and electrically heated. The heat is then transferred to the surrounding area of water which causes the light to bend, adequately making anything behind it appear invisible.
Invisibility cloaks using metamaterials use concentric gold rings that are injected with polarized cyan light to effectively divert incoming light waves away from the object to make it appear invisible. As of 2014, this technology is expected to be used to hide stationary objects, such as buildings and tanks, rather than to hide humans.
As of 2014, the final type of invisibility cloak made with optical camouflage technology is the only one that is actually wearable as a garment. It creates an optical illusion using a highly reflective garment and a variety of computers, cameras, projectors and mirrors. All of these objects work together to send computer-generated information to a person's sensory perceptions with the aid of a viewing apparatus. The result is that the viewer's brain is "tricked" into not seeing the hidden object.Learn more about Reference Books
Powder metallurgy is the process that creates metallic parts by mixing powdered metals into the desired shape and then heating the build. The process is divided into four steps: producing the powder, mixing the powder, compacting it and sintering it.Full Answer >
Another word for "babysitter" is caregiver. Additional synonyms, though differing slightly in employment duties, include child-minder, nanny, governess, au pair, child care worker and day care provider.Full Answer >
Old encyclopedias can be donated to local libraries, English as a second language schools, theater groups, prisons and artists. Libraries sometimes accept encyclopedia donations for their used book sales and use the profits to purchase new books.Full Answer >
The tablet that the Statue of Liberty holds in her left hand is inscribed with the date "JULY IV MDCCLXXVI" – July 4, 1776. The bronze plaque on the statue's pedestal has the text of the poem "The New Colossus" by Emma Lazarus engraved upon it.Full Answer >