1
00:00:00,370 --> 00:00:13,369
Well, today we are going to explain pulleys that are simple machines that can help us to lift objects easier.

2
00:00:13,369 --> 00:00:23,019
So, this is one of the simple machines.

3
00:00:23,019 --> 00:00:32,020
In this figure you can see a pulley.

4
00:00:32,020 --> 00:01:03,509
And it always has a support where it is an axis and the axis is through a wheel. The wheel is the pulley and this pulley always has a road pass that usually goes through the wheel.

5
00:01:03,530 --> 00:01:38,469
In a simple play, it's always a dynamic equilibrium, which is that the addiction of the force is

6
00:01:38,469 --> 00:02:01,609
0 and the addiction of revolution is always 0 too. So the speed of movement is always the same. If you see in this

7
00:02:01,609 --> 00:02:17,590
draw we are where we we calculate the addiction of the forces and on the left

8
00:02:17,590 --> 00:02:29,449
there is always there's there's only two forces the the action forces of the the

9
00:02:29,449 --> 00:02:37,689
loss of the object and the stress of the rope and in the other hand on the right

10
00:02:37,689 --> 00:02:48,050
is always two forces that are the power of the force you have to do and the

11
00:02:48,050 --> 00:02:58,129
stress. If the rope is the same, the stress is the same. So the action and the

12
00:02:58,129 --> 00:03:13,909
power are the same because both of them are are the same of the stress of the rock we are we we

13
00:03:13,909 --> 00:03:36,979
could do the calculate using the revolutions. On the right hand there is a revolution that

14
00:03:36,979 --> 00:04:05,930
make they will and go to the to the left and it is expressed the the the the multiplication of

15
00:04:05,930 --> 00:04:18,930
stress and the radius of the wheel. And the other hand, on the left, the

16
00:04:18,930 --> 00:04:34,470
multiplication between the power and the radius makes the wheel to go to the

17
00:04:34,470 --> 00:04:49,029
right. So if both of them are the same and the wheel is the same too, so the radius is the same,

18
00:04:49,029 --> 00:05:07,680
actions and power have to be the same too. So, in conclusion, in all the Texas pulleys,

19
00:05:07,680 --> 00:05:37,180
the power is the same to the action but sometimes we use more than one play we can't use mobile

20
00:05:37,180 --> 00:05:50,139
plays and in this row you can see how it works and there is to play a fixed play

21
00:05:50,139 --> 00:06:03,360
we have already study and and the other one is the mobile play in a mobile play

22
00:06:03,360 --> 00:06:23,009
the actions is the same that to stress because it is holding by two two ropes I

23
00:06:23,009 --> 00:06:30,990
mean there are not two ropes in the same row but there are a two pieces of this

24
00:06:30,990 --> 00:06:45,670
rope. So the action is two stresses. In the fixed play the power is one stress and the rope is the

25
00:06:45,670 --> 00:07:06,079
same. So the power I have to do is the half of the action. We can ejections more

26
00:07:06,079 --> 00:07:25,279
than one mobile play a depends on how are they connected we can we can

27
00:07:25,279 --> 00:07:36,180
construction and different kinds of hoist. In this picture you can see two

28
00:07:36,180 --> 00:07:44,899
that are very important. In the first one the rope is not the same and as you can

29
00:07:44,899 --> 00:08:00,060
see you you you are helping the addiction and in the second one and you

30
00:08:00,060 --> 00:08:17,000
just only and are the are dividing the the addictions into a different number

31
00:08:17,000 --> 00:08:38,539
bars of rope. These different kinds of holes have many importance because it helps us to

32
00:08:38,539 --> 00:08:51,580
blows, very big blows, and we have just only to do less force.