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3 years ago

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

Physics

1 answer:

stepladder [879]3 years ago

7 0

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

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4 years ago

Please help Need good grade

ivann1987 [24]

Answer:

The other angle is 120°.

Explanation:

Given that,

Angle = 60

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We need to calculate the range

Using formula of range

$R=\dfrac{v^2\sin(2\theta)}{g}$ ...(I)

The range for the other angle is

$R=\dfrac{v^2\sin(2(\alpha-\theta))}{g}$ ....(II)

Here, distance and speed are same

On comparing both range

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4 years ago

The period of a sound wave coming from an instrument is 0. 002 seconds. What is the frequency of the sound? Hz.

Pie

The period is the time taken by the wave to complete an oscillation. The frequency of the given sound is 500 Hz.

<h2>Period:</h2>

It is the time taken by the wave to complete an oscillation. The frequency is inversely proportional to the time:

$f = \dfrac 1T$

Where,

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Learn more about Period:

brainly.com/question/842349

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The complete statement is

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