Give me a fulcrum and I can lift the entire Earth? !
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“Give me a fulcrum and I can lift the Earth. ”This is a famous quote by the ancient Greek physicist Archimedes, and it also serves as a declaration of success for today’s youth – a declaration filled with passion and confidence, enabling them to move forward fearlessly. Actually, this is the principle of torque. Torque is defined as the product of force and the lever arm. Torque summarizes all the laws that affect changes in the motion state of a rotating object; it is the physical quantity that changes the motion state of such an object. M=F*L. How can the principle of torque be understood from the perspective of energy conservation? ! To pry a huge object with a very small force, work must be done on the object, and the work done by the small force is not equal to the work done on the object, right? Isn’t energy not conserved? !
After discovering the principle of levers, Archimedes exclaimed, “Give me a fulcrum and I can lift the Earth.” Archimedes’ remark was merely a theoretical statement. The principle of levers states that: effort arm × effort = resistance arm × resistance. Here, the effort refers to the force that a person (in Archimedes’ case) can apply； The resistance is the mass of the Earth. Using the principle of levers, we can determine that: Force = (distance of resistance arm / distance of effort arm) × resistance. Assuming that Archimedes could generate a force of 100 kilograms, and the mass of the Earth is 6×10^24 kilograms, then: 100 = (distance of resistance arm / distance of effort arm) × 6×10^24. This gives us: distance of effort arm / distance of resistance arm = 6×10^22, so the distance of effort arm = 6×10^22 × distance of resistance arm. It’s clear that as long as we can find a lever long enough and a fulcrum such that the distance of the effort arm is 60 trillion times greater than the distance of the resistance arm, Archimedes would be able to move the Earth! But even if such a lever and fulcrum could be found, Archimedes would still need to be able to support the lever against both the Earth and the fulcrum, while also being able to reach the other end of the lever, with the weight of this lever being zero. To move the Earth by just 1 millimeter, Archimedes would have to push the lever a distance of 60 trillion kilometers, which is more than 4,000 times the distance from the Earth to the Sun! But what about the law of conservation of energy? !
If a force acts on an object and the object moves a distance in the direction of that force, then in mechanics it is said that this force has done work. Formula: W = F × S. The force applied and the distance over which it acts are different, but their product remains the same. I didn’t fully understand the theories of middle school physics
Dare to challenge the laws of physics?
It should be conserved; Archimedes traveled such a long distance, and the Earth is so large that it’s just one millimeter