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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.


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

This depends on many factors.


Explain Why blackboards are not scratched by chalk but by the sand embedded in the chalk?

Blackboards are typically made of a material that is softer than chalk, such as slate or porcelain. When you write on a blackboard with chalk, the friction between the chalk and the board causes the chalk to wear down and leave behind tiny particles of sand or abrasive material embedded in the chalk. These abrasive particles then scratch the surface of the blackboard as you write, creating marks that can be difficult to erase.


What is a blackboard site?

A Blackboard site is an online platform commonly used by educational institutions for delivering course materials, assignments, and communication between instructors and students. It provides a virtual space for hosting discussions, sharing resources, submitting work, and grading assessments.