Question

Explain how sharpening a knife changes is MA (mechanical advantage).

Answer 1

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.

Cheers