Search results
Results from the Health.Zone Content Network
Uses. Reusable writing surface on which text or drawings are made. A blackboard or a chalkboard is a reusable writing surface on which text or drawings are made with sticks of calcium sulphate or calcium carbonate, known, when used for this purpose, as chalk. Blackboards were originally made of smooth, thin sheets of black or dark grey slate stone.
Chalkboard scraping. Scraping a chalkboard (also known as a blackboard) with one's fingernails produces a sound and feeling which most people find extremely irritating. The basis of the innate reaction to the sound has been studied in the field of psychoacoustics (the branch of psychology concerned with the perception of sound and its ...
Writing lines is a long-standing form of school discipline, having survived even as other old punishments such as school corporal punishment and dunce hats fell out of favour in the 20th century. [2] In a 1985 study, over half of respondent teachers in an English-speaking country indicated awareness of the use of writing to discipline students. [5]
With her school shut because of the coronavirus, Tolu Alagba kneels as she copies down class notes from a communal village chalkboard, the closest thing to online lessons on an island with no ...
Composition. Calcite ( calcium carbonate) Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Chalk is common throughout Western Europe, where deposits underlie ...
Blackboard bold is a style of writing bold symbols on a blackboard by doubling certain strokes, commonly used in mathematical lectures, and the derived style of typeface used in printed mathematical texts. The style is most commonly used to represent the number sets ( natural numbers ), ( integers ), ( rational numbers ), ( real numbers ), and ...
Whiteboard. A whiteboard (also known by the terms marker board, dry-erase board, dry-wipe board, and pen-board) is a glossy, usually white surface for making non-permanent markings. Whiteboards are analogous to blackboards, but with a smoother surface allowing for rapid marking and erasing of markings on their surface.
A chalkboard eraser is a special type of eraser specifically used to erase chalk markings on slating paint (used on chalkboards and slates ). It is most commonly made of felt strips attached to a handle. Chalkboard erasers are typically broad and rectangular, intended to clear large areas for new content as part of a lecture or presentation.