The force we applied is directly proportional to area.the tools with sharp edges have small area so if we apply small force it acts effectively and cuts sharp edge tools are used for cutting
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sry force is inversely proportional to area
We know that Pressure is directly proportional to Force and inversely proportional to Area.

So, when the contact area of cutting tools is less, cutting can be done easily, because more pressure is applied even with less force.

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