![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
Why is Archimedes's lever principle the same type of shovel, what is the shovel?
The cutter support point is at the junction, and the hand is at the far end of the knife, so the power arm is stronger than the resistance arm. The shovel support is in the right hand (similar to fishing rod) and the left hand is near the fulcrum, so the power arm is less than the resistance arm.
Push up is a common fitness project. As shown in the picture, Xiao Ming's body can be seen as a lever, o point as a fulcrum, a point as the center of gravity, and the gravity is 500N (1) (2) if L1 = 2.1cm, L2 = 3.0cm, calculate the support force of both hands on the ground. (3) if the area of each palm is about 1.5 × 10-2m2, calculate the pressure of both hands on the ground
(1) As shown in the figure: (2) according to the condition of lever balance, we can get: f1l1 = f2l2500n × 2.1cm = F2 × 3.0cmf2 = 350n, so the support force of both hands is 350n. (3) according to the calculation formula of pressure, we can get: P = F2s = 350n
Push up is a common fitness project, Xiaoming students do push up, her body can be seen as a lever, O as the fulcrum, a as the center, gravity is 500N
(1) If L1 = 2.1cm, L2 = 3.0cm, calculate the support force of the ground opponent
(2) If the area of each palm is 1.5 * 10 negative quadratic, calculate the pressure of both hands on the ground
No picture, no truth, but I've seen it on the Internet
You can click ID to check in yakuka encyclopedia
Analysis of the answers to various mathematical problems in Physical Chemistry
If a classmate lives and does push ups, he can be regarded as a lever. His center of gravity is at point a, and the gravity is 500N. Then he will support his body, and the pressure of his hands on the ground is at least n (the distance from point a to his feet is 1m, and the distance from point a to his head is 0.7m)
My calculation result is about 294n, yes? I need a complete solution process
Let the man form an X angle with the ground
So in the process of rising,
Gravity = mg arm = 1 * cosx
Support force n arm of force = 1.7cosx
MG*cosx=N*1.7cosx
N=294.11N
RELATED INFORMATIONS
- 1. 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
- 2. How to draw physical lever diagram
- 3. 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
- 4. Solving the labor saving principle of moving pulley
- 5. Please explain the working principle of the movable pulley
- 6. Using the lever theorem, Give you a pen, a meter ruler, and some 50g weights to calculate the mass of the ruler
- 7. 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
- 8. 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?
- 9. When to use Archimedes theorem to calculate
- 10. Where is the insulating paint scraped away from the resistance wire on the rheostat? Why?
- 11. Briefly talk about the similarities and differences of the use of lever principle between pliers and guillotine
- 12. 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
- 13. 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----
- 14. 1. Heat the white sugar in the pot until it turns black, and taste whether the black substance is sweet or not? 2. Take desiccant bag, add tap water and test its temperature change? 3. Take rust iron nail and white vinegar reaction 4. Take the polished nails and white vinegar to reflect 5. Take the outer metal skin of the battery and white vinegar to reflect 6. Add water to the battery contents, soak garlic, and test its germination, which is different from that of water 7. Take alkali surface and add white vinegar for reaction 8. Take different petal juice, add white vinegar and alkaline water to react
- 15. 1. Heating potassium permanganate to produce oxygen, the safe operation after the end of the experiment is first (), and then () 2. The function of ice water in water tank is () 3. It is proved that in the reverse catalysis test of hydrogen peroxide, 1.（ ） 2. Put manganese dioxide into large test tube and add 5ml hydrogen peroxide 3. After the reaction, filter, wash, dry and weigh the solid substance in the large test tube 4.（ ） After finishing this experiment, we need to prove the catalytic effect of manganese dioxide, and add an inquiry experiment: Inquiry () 4. The factors that affect the rate of chemical reaction may be ()
- 16. What kind of lever is the balance? What principle does it use?
- 17. Why should the balance beam be made equal arm
- 18. What factors are related to the mechanical efficiency of leverage
- 19. What are the rules of mechanical efficiency of pulley block? The more hook yards, the greater the mechanical efficiency
- 20. In the experiment of exploring the mechanical efficiency of pulley block, what is the experimental principle