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because they are black and they are a board.

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15y ago

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Why blackboard called blackboard instead it calledgreen board?

The term "blackboard" originates from the traditional color of the writing surface, which is typically black or dark gray. This color allowed for high contrast with white or colored chalk, making it easier to read from a distance. While modern boards can be green or other colors, the name "blackboard" has persisted due to historical conventions. The green board, often referred to as "greenboard," is just a variation that became popular later.


Who uses a blackboard and chalk?

I am pretty sure it's a teacher.


What is the attraction between unlike molecules such as chalk and blackboard?

The attraction between unlike molecules, such as chalk and a blackboard, is primarily due to electrostatic forces. When chalk is rubbed on a blackboard, it can create a transfer of electrons, leading to the buildup of static charges. This charge difference generates an attractive force between the two surfaces, allowing the chalk to adhere to the blackboard. Additionally, van der Waals forces may also play a role in the interaction between these materials.


What some physical properties of a blackboard?

A blackboard typically has a smooth, matte surface that is designed to minimize glare and allow for clear visibility of chalk markings. It is usually made of materials like slate or a composite that can withstand repeated writing and erasing. The color is predominantly black or dark green, which enhances contrast with white or colored chalk. Additionally, blackboards are relatively heavy and sturdy, allowing them to remain stable when mounted or placed upright.


How long does it take for water to evaporate on a blackboard?

This depends on many factors.