Are compact discs compact enough for you?
- A compact disc is a thin optical disc, used primarily to store digital information, and it is also commonly called a ‘CD’.
- Compact discs are circular in shape, with a central hole, and are made of plastic, that is usually coated with aluminium or gold for reflecting the laser that ‘reads’ the disc, and then a layer of lacquer is applied for protection.
- The storage space of compact discs usually has a maximum capacity of 700 MiB – mebibytes (734 MB – megabytes) of data, in the form of programs, media or information, which equates to approximately 80 minutes of audio.
- The typical size of a compact disc is 12 centimetres (4.7 inches) in diameter, although they can be as small as 6 to 8 centimetres (2.4 to 3.1 inches) in diameter.
- American James Russell was the inventor of the optical digital recording and playback concept that is used in compact disc technology, which he designed in 1966, and he received a patent for the system in 1970.
- In 1979, the companies Philips and Sony, formed an unusual working relationship, using James Russell’s concept, to together develop a compact disc, and in 1982 the first CDs were manufactured, being the ABBA music album The Visitors.
- A compact disc spins when it is placed in a CD player or drive, and as it does, it is read by a laser that interprets the miniscule indents, called ‘pits’, invisible to the naked eye, found on the plastic layer of the disc.
- Compact discs were originally designed to emit sound, however, in the 1980s it was realised that the disc could be used for a variety of purposes, including the storage of computer data.
- Compact discs are usually purchased in a protective sleeve, like a hard plastic case; a paper packet; or a soft plastic envelope.
- By 2007, world sales of compact discs had reached 200 billion, although sales have decreased significantly in recent years, due to digital technology and streaming; and in the music industry, 2014 marked the first year CDs were outsold by streaming technology.
Do you undersand the wonders of sand?
- Sand is a group of rocks and minerals that have eroded into fine, minuscule grains; and large quantities of the substance is often found on coastlines and in desert areas.
- Sand can be composed of a variety of items, including particles of calcium carbonate, coral, quartz and shellfish.
- A sand grain can be defined as a particle that is between 0.06 and 2 millimetres (0.002 and 0.08 of an inch) in diameter, and is smaller than a piece of gravel but larger than a speck of silt.
- The colour of sand varies greatly, depending on its location and the rocks and minerals that make up the particles, although it is commonly observed to be white, brown, tan, cream, red, grey or black.
- The unique shape of a piece of sand can help determine its source and age, while more pronounced angles often indicate a more recently formed grain.
- Some individuals collect samples of sand as a hobby, and these people are called ‘arenophiles’.
- Sand is one of the primary components of soil, and the ratio of sand to clay and silt, partly determines the quality of the soil.
- Dry sand can be dangerous if inhaled, so caution must be taken while using machines such as sandblasters.
- Due to the weight of sand, bags of the substance can be used to keep objects stationary by weighing them down, or it can be placed inside an item to make it heavier.
- Sand has many applications and is used for concrete and brick making; is the main ingredient in glass making; and is often used for entertainment purposes, especially by children to play in, or make sand castles or other structures, due to its ability to be shaped when damp.
Be well read with enough information to fill many books.
- A book is a bound collection of sheets or pages, used for record keeping, or conveying information that generally entertains or informs.
- The pages of books usually contain printed text or illustrations, or they can be blank so that they can be written in by hand, while sometimes the pages will feature a combination of these characteristics.
- Paper is the most common material used to make book pages, and the text is usually printed on the page.
- In ancient history, the first books were made of tablets of stone, metal, bark or clay, and this medium was used during the Bronze and Iron Ages.
- Papyrus, a plant material, was used to create books, or more accurately scrolls, by Ancient Egyptians from around 2400 BC; and parchment, a product made from animal skin was also used in ancient times.
- Before the revolutionary invention of Johannes Gutenburg’s printing press in the mid 1400s, ‘mass production’ of books was performed by wood-printing techniques.
- ‘E-books’ are those that are available in electronic form, and this is becoming an increasingly popular way of obtaining books, while numerous electronic devices and tablets are engineered to support these electronic versions.
- Books are available in a wide variety of sizes and thicknesses according to their purpose and number of pages, although they are mostly orientated to sizes that the printing and paper allow for.
- Books are commonly obtained by purchasing them from retail outlets or borrowing them from a library.
- In 2010, Google announced that there were approximately 130 million individual book titles that had existed in modern history up until that time.
Do you get frustrated wrapping up food with plastic wrap?
- Plastic wrap is an invention that is generally used to cover food objects and keep them airtight, or to bundle loose items.
- ‘Plastic wrap’ is also known as ‘Glad wrap’, ‘cling film’, ‘Saran wrap’, ‘cling wrap’ and ‘food wrap’.
- Typically, plastic wrap is rolled around a cylinder that is purchased in a box, that generally features an attached, toothed metal bar for cutting.
- Plastic wrap was originally made of polyvinyl chloride (PVC) plastic, which is notoriously hard to recycle and its toxicity has been questionable, however low density polyethylene (LDPE) is becoming more common, and manufacturers have been continually improving their products to create totally non-toxic food wraps.
- Plastic wrap is commonly used to cover plates, bowls or other dishes, especially leftovers, to protect and seal the food they contain, often for storage in the refrigerator.
- The accidental invention of plastic wrap in 1933 is attributed to Ralph Wiley from Dow Chemical, and the substance was originally used by the military as a spray on planes and other vehicles, to protect them from rust and other deterioration.
- Plastic wrap usually sticks to itself, and it also generally adheres to smooth surfaces, making it a flexible system for sealing all sorts of items of varying shapes and sizes; and wrap with similar qualities is used to bind items as small as a rolled newspaper, or as a large as a pallet-load of goods.
- Plastic wrap was not developed as a food wrap until 1949, when it was first used in the food industry, and it was not until 1953 that it was available for home use.
- Plastic wrap boxes usually have tabs on either end of the box, that can be pushed inside the box to hold the roll in place as the wrap is pulled from the roll.
- Plastic wrap for home use usually comes in rolls that are 29 to 33 cm (11.5 to 13 inches) wide, and in varying lengths from 15 to 150 metres (16.4 to 164 yards), although much wider and longer rolls are available in the catering industry.
How long can a fire burn in the Door to Hell?
- The Door to Hell is among the largest deposits of natural gas in the world, located in the Karakum Desert in Turkmenistan’s Derweze, in Asia.
- ‘The Door to Hell’ is also known as ‘Gates of Hell’, the ‘Gas Crater of Darvaza’, ‘Derweze Crater’ and the ‘Darvaza Crater’.
- The Door to Hell gas field is said to have been discovered by petrochemical engineers from the Soviet Union in 1971 and a drilling rig was soon established.
- Early on, during the gas drilling stage at the Door to Hell, the site collapsed and formed a 69 metre (225 feet) diameter hole, that is 30 metres (99 feet) deep.
- When the collapse at the Door to Hell occurred, large quantities of toxic and non-environmentally friendly methane gas were released, which to remove, was set alight.
- The original fire of the Door to Hell is said to have been burning since 1971, although at the time, it was expected that the fire would only last a few days or weeks.
- In late 2013, adventurer George Kourounis, a Canadian, reached the Door to Hell’s base, becoming the first person to accomplish this, and he collected soil samples from within that contained extremophile bacteria.
- To protect and allow future gas mining in the area, the Door to Hell was commanded to be closed in early 2010, by Turkmenistan’s then President Gurbanguly Berdimuhamedow, although it was not accomplished.
- The nearby town of Derweze is said to have had a forced population reduction from approximately 1,700 people, to 350 in 2004, by the then President Saparmurat Niyazov’s orders, to ‘protect’ the tourism industry of the Door to Hell.
- The Door to Hell is a popular tourist attraction for those visiting the area, with people venturing onto the crater’s edges, which are susceptible to collapsing, to view the spectacular fires in the crater.