In the balance, car brake pedal, sewing machine pedal, iron scissors, barber scissors, cloth scissors, guillotine, driver, fishing rod, tweezers, wrench, chopsticks, claw hammer, trolley, steel wire pliers. Among them, 1: belongs to labor-saving lever; 2 belongs to labor-saving lever; 3 class arm lever
Belong to the labor-saving lever: car brake pedal scissors iron scissors knife driver wrench
Claw hammer, handcart, wire pliers
The utility model belongs to a laborious lever; a sewing machine, a pedal, a hairdresser, a scissors for cutting cloth, a fishing rod and tweezers
chopsticks
Equal arm lever: balance
RELATED INFORMATIONS
- 1. For a 2.2m long wood with uneven thickness, one end is placed on the ground, and the force of 680n is needed to lift its thick end; if the thick end is placed on the ground, the force of 420N is needed to lift its other end? (2) The position of the center of gravity of the wood
- 2. When a moving pulley is used to lift a 500N object at a constant speed, the pulling force F is () n, and the pulling force on the hook of the moving pulley is () n
- 3. Is pulley a lever Why is pulley a deformation of lever? Isn't lever a hard rod? Can you make it clear
- 4. Lever and pulley Now that we have learned lever, we know that lever can be divided into labor-saving lever, equal arm lever and labor-intensive lever. Why should we introduce pulley? What are the advantages of pulley compared with lever?
- 5. There is a fulcrum O in two shoulder poles ab of the same length, OA ≠ ob, Ma = MX in Figure 1 and MB = MX in Figure 2. Find the value of MX A__________ o___ B | | | | mx mb A__________ o__ B | | | | ma mx Find what MX equals,
- 6. The problem of tree planting is the same as the problem of tree planting, but the topic is not the same The corridor of a dormitory is 15 meters long, with four colored flags. According to this calculation, the corridor of an office building is 27 meters long, how many colored flags should be inserted &It takes eight minutes to saw a piece of wood into three sections. If the time for each section is the same, how many minutes does it take to saw seven sections? &Uncle Zhang is walking on the path full of telephone poles at the same speed. It took him 22 minutes to walk from the first telephone pole to the 12th telephone pole. If he walked for 36 minutes, which telephone pole should he walk to?
- 7. Solving linear equation with one variable Wuhan plans to plant trees on one side of a certain section of the road. It requires one tree to be planted at both ends of the road. If one tree is planted every 5 meters, 21 seedlings will be missing. If one tree is planted every 6 meters, the seedlings will be used up. How many seedlings are there?
- 8. The total length of a bridge is 161 meters. It is planned to install 16 billboards on the railings on both sides of the bridge. The length of each billboard is 2 meters. The billboards at both ends are 12 meters from the bridge end. The distance between two adjacent billboards is equal. The distance between two adjacent billboards is calculated
- 9. A and B plant trees. It takes 13 more time for a to plant this batch of trees alone than B. if they work together, B will plant 36 more trees than a when they finish the task. How many trees are there in all?
- 10. Next to a straight runway, 51 flags were planted, with an interval of 2 meters. Later, only 26 small flags were planted, with an average interval of how many meters? (both ends are inserted)
- 11. In the following statements about leverage, the correct one is () A. The fulcrum is always between the power action point and the resistance action point. B. the longer the power arm is, the less labor is always saved. C. the direction of power action is always opposite to that of resistance action. D. the larger the ratio of power arm to resistance arm, the less labor is saved
- 12. On December 5, 2009, on the eve of the United Nations Climate Change Conference, an artist created an arctic bear ice sculpture (as shown in the picture) in a square in Copenhagen, Denmark. During the conference, the ice sculpture will gradually melt, revealing the copper skeleton. The organizers hope to arouse people's attention to global warming through the melting of the ice sculpture The contact area between the polar bear ice sculpture and the base is 1.2 m 2. Calculation: ① the mass of the ice used by the artist; ② the total gravity of the polar bear ice sculpture; ③ the pressure of the polar bear ice sculpture on the base. (ρ ice = 0.9 × 103 kg / m3)
- 13. The sum of number a and number B is 210, and 13 of number a is equal to 14 of number B?
- 14. Mathematics classic questions of grade six in primary school Help, please!
- 15. Do real problems or 400 problems in mathematics first? RT starts to do math papers in the rest of the day. Do you want to do real problems or 400 problems first?
- 16. If a, B and C are real numbers which are not equal to each other and satisfy the relation B2 + C2 = 2A2 + 16A + 14 and BC = a2-4a-5, then the value range of a is______ .
- 17. How to write the prediction composition of sixth grade life How to write a composition
- 18. Change my life
- 19. Recalling my primary school life composition
- 20. The unforgettable things in sixth grade composition Tell me what theme to write, it's better to have a model essay, it's better to understand a truth from it