Question

IS IT POSSIBLE TO WRITE PROPERLY WITH A PIECE OF CHALK ON A GLASS SHEET? WHY OR WHY NOT?

Answer 1

Not possible.

Friction is very less on glass sheet. When we try to write on it our hand will slip. A blackboard provides that required friction to chalk.

Answer 2

The glass sheet is a smooth surface. The friction that a piece of chalk faces on a glass sheet is much lesser than what it may face when used to write on a board. Hence, the writing is not clear in the case of a glass sheet when used as a writing surface.