Which pulley is the force of pulley block

1. The moving distance of power end is related to the number of load-bearing rope segments - if the number of load-bearing rope segments is n and the weight rises h, then s = NH
the key is to find out the number of load-bearing rope segments
for reference only!

2. The fixed pulley does not save labor, and the movable pulley saves labor to 1 / several times of the original force according to the number of strands of the rope around it. Its essence is lever balance, that is, boom × Power = drag ratio times drag. The answer is over. Please accept it.

3.

There are many islands scattered in the sea area, which can be captured. The islands can go to or transmit by themselves or through different land

First of all, you need to open the big map in the upper left corner of the game to find the middle and upper part of Nanshan, near Zhongshan,

4.

1. In fact, the official way is to apply for a visa, just from the port

2. In the game map, we can find ports, for example, in the land near the sea, on the edge of the desert

3. At the port, we can see the corresponding NPC, and the visa officer can let us choose to go to other continents

Second, "illegal immigration"

1. In addition to official channels, we can also illegally cross the border

2. If we swim along the continental margin, we can sneak across, but we should pay attention to that the players who sneak across will be hunted

5.

The method of winding the pulley block is to meet the stress requirements, and the rope is smooth without knot ring operation. The way to distinguish moving pulleys in a pulley block is to see whether the position of the pulley shaft moves with the object being pulled

some common winding methods are as follows:

the movable pulley can be regarded as a labor-saving lever, O is the fulcrum of the lever, and the axis of the pulley is the action point of resistance. The force of the lifted object on the shaft is resistance, and the force of the rope on the wheel is power. When lifting heavy objects, if the ropes on both sides are parallel, the power arm is twice the resistance arm

When the moving pulley is balanced, the power is half of the resistance. Therefore, if the gravity of the movable pulley is ignored, half of the force can be saved by using the movable pulley, but the direction of the force can not be changed at this time, and the heavy object can only be lifted by pulling the rope upward

extended data:

the pulley block is made up of several fixed pulleys and movable pulleys, which can save labor and change the direction of force. In use, the amount of labor saved and the winding method of the rope depend on the use effect of the pulley block

the moving pulley is borne by several ropes, and the force is a fraction of the total weight of the object and the moving pulley

The principle of

is: when

n is odd, the rope driven pulley is the starting point. When a movable pulley is used, there are three sections of rope to bear, and then two sections of rope are added for each additional movable pulley

If n = 5, two movable pulleys (3 + 2) are needed. When n is even, the rope starts from the fixed pulley. At this time, all moving pulleys are only supported by two pieces of rope. For example: n = 4, two movable pulleys (2 + 2) are required

Secondly, the number of fixed pulleys should be determined according to the requirements. The principle is that a moving pulley is generally equipped with a fixed pulley. When the direction of force action is not required to be changed, a fixed pulley can be reced for even section of rope; In order to change the direction of force, a fixed pulley should be added

To sum up, the design principles of pulley block can be summarized as follows: odd dynamic couple fixed; The movement matches certain, the even number subtracts certain, the change direction adds certain

6. Two are fixed pulleys and two are movable pulleys. The reason for saving labor is the same as the principle of lever, except that its arm of force is not straight. However, you can also imagine that a heavy object is connected by two sections of rope first. If each section only receives half of the force, and then half of the force is divided into several forces, we only need to use a small force to OK, It saves a few parts of the weight

7.

s=nh V rope = n * V object f pull = (1 / N) * g total

s: the distance of the free end of the rope moving. V rope: the speed of the free end of the rope moving (up / down)

H: the height of the weight being lifted. V object: speed of object moving (ascending / descending)

n: number of load-bearing rope segments (rope connected with moving pulley). G total: weight of material + weight of pulley (g material + G sliding)

when using the pulley block, the pulley block uses several sections of rope to lift the object, and the force used to lift the object is a fraction of the weight of the object. The force acting on an object; The distance a body passes in the direction of a force

extended data:

the essence of the fixed pulley is an equal arm lever, and the power arm L1 and resistance arm L2 are equal to the pulley radius. According to the lever balance condition, it can be concluded that the fixed pulley does not save labor and distance

when the pulley block is used, the distance m transported by the power unit is L / K when the pulley block is not used. In order to facilitate the comparison, the power unit in two states can work K times respectively. In this way, the power unit with the pulley block can transport the goods with the mass of k2m 'to the distance L, while the power unit without the pulley block can transport the goods with the mass of KM' to the distance L

at this time, it can be seen from the comparison that the mass m of the object m 'transported by the power unit when the pulley block is used is k times of the mass m' of the object m 'transported by the power unit when the pulley block is not used

8. Ask
does the network know the labor saving principle of pulley block
pulley block is composed of movable pulley and fixed pulley. The force of moving pulley and fixed pulley can be explained by lever principle. What about the pulley block? For the pulley block illustrated in the figure below, only one third of the force is needed in ideal condition. Can we use the lever principle to explain it<

please don't and paste. I beg you to give me an answer. Thank you for your help
or now
Lv. 8 May 22, 2017

the essence of lever principle is explained by functional principle. When using machinery, people do work directly by hand instead of using machinery, that is, using any machinery does not save work
here, raise one end of the rope, set the height to L, and the object only moves 1 / 3 of the increased distance, And work = force times distance, so FL = MGL / 3, so force is mg / 3, saving effort must cost distance, the proct of the two is work is constant, corresponding to the ideal (frictionless) machinery
it can also be understood that the rope is static, its tension is f everywhere, in order to maintain the balance of static, the object is pulled by three pieces of rope, each piece of force is f, so 3F = mg

9.

Summary of the most labor-saving rope winding method of pulley block:

from the above questions, we can roughly summarize the following several most labor-saving rope winding methods of pulley block:

1, The two methods have achieved the goal of labor saving, but the direction of tension is different. There are three winding methods, the direction of tension is upward; There are two ways to wind the wire. The pulling force is downward. The most correct way is to fix one end of the rope on the movable pulley at the top of the lower side, and then go up and around the fixed pulley at the bottom of the upper side, and finish the winding from the inside out in turn. After winding, the free end of the rope should be pulled up (the number of movable pulley and fixed pulley is equal). For the pulley block composed of two movable pulleys and one fixed pulley, the rope is first tied on the fixed hook of the fixed pulley, and the pulleys on the winding pulley block are all used, with four strands of rope to bear the weight; The pulling force is one fourth of the weight of the block. The most labor-saving winding method of pulley block is the one with the largest number of strands, that is, the four strand winding method. As shown in Figure 2

3. The labor-saving winding method of two moving and two setting four-wheel pulley block, The moving pulley and weight are borne by several strands of rope, and the pulling force is a fraction of the lifting weight of the pulley block. The labor-saving situation of the pulley block depends on the number of segments of the rope that bears the weight of the object. That is to say, several segments of the rope are connected with the movable pulley. The more segments, the more labor-saving. For example, legend 3

these are only the number of pulley blocks that we need to use in junior high school physics. In senior high school physics, we may also contact five pulley blocks, six pulley blocks or even more pulley blocks. However, no matter how many pulleys there are, as long as we master a few essentials, we can not worry about the increase of the number of pulleys

Generally speaking, when winding the pulley block, first determine the rope strand that bears the weight, and then wind the rope according to the principle of odd and even from the inside out& quot; "Odd" and "even" refer to the number of strands of the rope that bear the weight of the object; "Moving and fixed" refers to the moving pulley and fixed slip, that is, if n is odd, the starting end of the rope starts to wind on the small hook of the moving pulley; If n is even. Then the rope starts to wind on the hook of the fixed pulley. It should be noted that: when winding. Draw a straight line. And it should be tangent to the two sliding sides; In general. Mark the direction of the pull with an arrow at the end of the last (outermost) strand

through the above explanation on the labor-saving rope winding methods of several pulley blocks, do you think that the winding of pulley block is not as difficult as you think

for more information, please refer to the labor saving pulley

10. The problem of determining the relationship between the tension at the free end of the rope and the gravity of the weight according to the actual drawing of the pulley block or the schematic diagram of the pulley block is actually to solve the problem of labor saving of the pulley block (that is, how much force is saved? Or F =? G) It is also a problem of how much n is.
① the pulley block has several strands of rope to bear the weight of the object, and N is how much. Of course, the tension at the free end of the rope is 1 / N of the weight of the object; When the free end of the rope finally bypasses the moving pulley, it will bear the weight.
② the method to judge how many strands of rope bear the weight: as shown in the figure, draw a dotted line between the fixed pulley and the moving pulley, and count the number of strands n of the rope bearing the weight, that is, the number of strands n of the rope intersecting with the dotted line (Note: the strand of the rope that the free end of the rope finally bypasses the fixed pulley is not included! Because it doesn't bear the weight