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Now we are going to study the livers. That is another simple machine which has a lot of different applications in our days.

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A lever is a simple machine which consists in a rigid bar which is divided into two pieces or two parts by a support called fulcrum.

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In one of the parts we have to project a force which usually called power.

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This force, we usually do this force in order to move some different weights or different forces that usually cause resistance.

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The liver, like another simple machine, always plays the dynamic equilibrium, which consists in the addiction of the forces.

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uh has to be it has to be uh oh and the addiction of the movement has to be

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oh too and that's um that means that the the speed of the movement is always the same it's constant

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and we all we just only have to to do a little bit of force when we have to change and the the

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the speed so at the beginning of the movement but it is it is not it's not all the the truth

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because we always lost some energy because we have some losses of energy in the machine.

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However, in the simple machine, the losses of energies are very low, so they could be like this.

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In other machines we have to do not only this addiction of forces, we have to do the energy balance to know how works the machine.

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but to but in this case for our students that is enough they only have to know

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the addiction of forces and addiction and movement finally and we always say

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that the delivers law is a consequence of the addictions of movement and you

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can see it is in this presentation that the the probably when we multiply the

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resistance for the distance of the resistance to the fulcrum which always

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called the resistant arm, this multiplication has to be the same

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that the multiplication between the power and the distance of the powers to

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This is the liver law and sometimes it's usually very important because we have always to do less resistance than we have to do if we don't use the liver.

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and that is the main advantages to the diverse.

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The leaders are divided into three genders,

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and these genders are different between where are fulcrum, power and resistance.

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The first of the genders, for example, the rocker, will always have the fulcrum between the power and the resistance.

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The second gender has got the resistance between the power and the fulcrum, and one of the examples is the barrow.

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Finally, the third gender has got the power between the resistance and the fulcrum.

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One of the more important examples could be the teenagers.