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In this presentation, we are going to explain what is a pulley and their different types.

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A pulley is a simple machine which helps apps to lift up, apply forces and transmit power.

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And the transmission of the forces usually do using a rope. It is very important that the force which makes rope stress, cold stress.

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While the rope is the same, the quantity of force is the same too, and it helps us to

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know and to calculate and how much is the force that we are have to do to lift

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up some lows. In this figure you can see a pulley and it always have a support

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where it is an axis and the axis is through a wheel. The wheel is the pulley

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and this Poulet always have a row path that it always that usually called

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In a simple play, it's always a dynamic equilibrium, which is that the addiction of the force is

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O and the addiction of revolution is always O too. So the speed of movement is

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always the same if you see in this draw we are we are we we calculate the

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addiction of the forces and on the left there is always there's there's only two

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forces. The action forces of the load of the object and the stress of the rope.

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And in the other hand, on the right, there is always two forces that are the power of

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the force you have to do and the stress. If the rock is the same, the stress is the same.

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So the action and the power are the same because both of them are the same of the stress of the

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work. We could do the calculates using the revolutions. On the right hand there is a

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a revolution that makes the wheel go to the left, and it expresses the multiplication

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of stress and the radius of the wheel. And the other hand, on the left, the

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multiplication between the power and the radius makes the wheel go to the

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right. So if both of them are the same and the wheel is the same too, so the radius is the same,

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actions and power have to be the same. So, in conclusion, in all the Texas pulleys, the power

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is the same to the action but sometimes we use more than one play we can't use

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mobile place and in this row you can see how it works and there is to play a

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fixed play we have already study and and the other one is the mobile play in a

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mobile play the actions is the same that to stress because it is holding by two

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two ropes. I mean, they are not two ropes in the same row, but they are two pieces of this rope.

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So the action is two stresses. In the fixed play, the power is one stress and the rope is the same.

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So the power I have to do is the half of the action. We can ejections more than one mobile

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play a depends on how are they connected we can we can construction different

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kinds of hoist. In this picture you can see two that are very important. In the first one the rope

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is not the same and as you can see you are helping the addiction and in the second one

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and you just only are dividing the addictions into a different number of ropes and these

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These different kinds of holes have many importance because it helps us to load a very big load

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and we have just only to do less force.