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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
The purpose is to measure the length of the arm of force easily, because the arm of force coincides with the lever only when it is balanced in the horizontal position
Power arm resistance arm
The purpose is
Fixed position, labor saving
Why should the lever be balanced in a horizontal position? What is the purpose of doing so?
In the experiment of studying the balance condition of the lever, the distance between the force point and the fulcrum is the size of the two force arms only when the lever is balanced in the horizontal position
1. How to balance the lever in horizontal position?
2. After adjusting the lever, why is it not allowed to rotate the nuts at both ends?
If the force on both sides of the arm is equal, the direction of the force should be the same. The lever will be balanced in the horizontal direction
If the nuts at both ends are adjusted, the arm of force on the side to be adjusted will increase. When both sides are balanced, the arm of force * on both sides are equal, so the change of arm of force directly affects the balance of lever
The main purpose of adjusting lever to balance in horizontal position
Is it convenient to measure the arm of force directly on the lever, or to avoid the influence of the gravity of the lever itself on the experiment? If both exist, under what circumstances do they appear? In the first test, I filled in the left side, and the answer was correct on the right side; in the second test, I filled in the right side, and the result was correct on the left side, so I felt very strange,
Function before adjustment: the lever weight has no influence on the balance of the lever. Function during experiment: it is convenient to measure the arm of force
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