Please explain the working principle of the movable pulley

It can be seen from the drawing that the diameter of the pulley is regarded as a lever, one end as a fulcrum, the center as a resistance action point, and the other end as a power action point. In this way, the power arm is twice as much as the resistance arm, so it saves effort

What tools in life use leverage

Chopsticks, scissors, cold clothes, sticks, shovels, woks and so on are all related to the lever principle

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1. Using the lever theorem, Give you a pen, a meter ruler, and some 50g weights to calculate the mass of the ruler
2. Archimedes's famous saying, as long as we give him a fulcrum on the earth, he can pry up the earth. What's the reason
3. Archimedes, a famous ancient Greek scholar, once said, "if you give me a lever and a fulcrum, I can pry the earth." Now let's make a hypothesis that C is the fulcrum, and the lever can rotate around C. We put the earth at point B. if the ratio of the power arm AC and the resistance arm BC of the lever is 5:1, and we want to lift the earth up 10 cm, how many m should we press the A end of the lever down?
4. When to use Archimedes theorem to calculate
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6. 1000 ohm = - megaohm, the structure of sliding rheostat -, -, -, -, -, -
7. How to judge whether sliding rheostat is current limiting connection or partial compression connection
8. What do you think of the circuit diagram of the sliding rheostat? What is the current direction? What is the physical diagram? Why do you want to connect three terminals? What's the current direction? What's the physical picture? Why do you want to connect three terminals? I'm not sure!
9. Marxist philosophy is the philosophical foundation of the theory of building socialism with Chinese characteristics
10. The relationship among the theoretical system and system of the socialist road with Chinese characteristics
11. Solving the labor saving principle of moving pulley
12. Schematic diagram of forceps force lever Why is forceps a hard lever? Why is the fulcrum the top? Please help draw the diagram of the forced lever and explain it in detail
13. How to draw physical lever diagram
14. Push up is a common basic exercise. Xiaoming weighs 600N. He does 30 push ups in 1min. Every time he does it, his shoulder rises 50cm. Xiaoming's body is a lever, and O is a key If the area of each palm is 0.016 M & sup2;, calculate the pressure of both hands on the ground and the work done by Xiaoming in 3.1 Min. 4
15. Why is Archimedes's lever principle the same type of shovel, what is the shovel?
16. Briefly talk about the similarities and differences of the use of lever principle between pliers and guillotine
17. Hang two groups of hook codes on both sides of the lever, adjust the number of hook codes or the position on the lever, so that the lever is balanced in the horizontal position. What is the purpose? Record___ 、___ 、____ 、______ Then hang a group of hook codes on the same side of the spring dynamometer, and the spring dynamometer should be pulled vertically upward for the purpose of? In use__________ The fixed pulley is called the fixed pulley_____ But you can____________ And change the direction of tension
18. In the experiment of studying lever balance, the nuts at both ends of the lever should be adjusted so that the lever is balanced in its original position. At this time, when the lever is still balanced in its original position after the two ends of the scale are hooked, the distance from the point of action of the force to the fulcrum is equal to that of the force----
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