Q. 33.9( 7 Votes )
To sharpen the blade of a knife by rubbing it against a surface, which of the following will be most suitable?
B. plastic block
C. wooden block
D. glass block
To sharpen the blade of a knife, rubbing it against the surface of a stone will be the most suitable.
⇒ Friction increases when the surface is rough.
⇒ Stone has rough surface among all.
⇒ When you rub the knife against it, it will exert greater reaction.
⇒ As a result, the force of friction will increase and the knife will become sharper.
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