Answer:
Sharpening a knife reduces it's height as a wedge thus giving it more efficiency.
Explanation:
Mechanical advantage refers to the degree or quantity to which a force is increased or amplified by using a tool or a machine.
Mechanical Advantage can be calculated as follows:
Lenght of Incline (LI) / Height of Incline (HI)
Assume I have constructed a hedge with an inclination that run 10 meters from point x to point y (which is the back of a truck. Point y to the floor is 5 meters.
If LI = 10m and
HI= 5m
The mechanical advantage is given as 10/5 = 2
The angle of incline is also called the effort distance. From our calculations above, by sacrificing horizontal movement, I reduced the amount of effort it would have cost to lift up that object from ground up - a distance of 5 meters.
Think of a knife as a form of a similar wedge.
The more a knife is sharpening of a knife further reduces its angle of elevation. Thats why it becomes more efficient to use, hence our mechanical advantage.
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