Homemade catapult - the role of levers

Observation and Exploration:

1. Let's guess a riddle: Two people ride a horse, one side is high, the other is low; The horse does not walk, but the two ride happily.

2、As the saying goes: 'A small weighing scale can bear a thousand pounds,' the pole scale is a measuring tool invented by our ancestors, with a history of over four thousand years. Do you know the reason behind it?

Have you ever watched the NBA? Do you envy the players' agile skills? Today, the basketball shooter we are going to make can help you fulfill your dream of becoming a basketball star. Knowledge point:

1. Lever: A rigid bar that rotates around a fixed point under the action of a force is a lever.

2. Lever's Five Elements: Fixture Point, Power, Power Arm, Resistance, Resistance Arm.

3. Lever balance condition: the force multiplied by the force arm equals the load multiplied by the load arm.

4. Levers are divided into three types: lever of ease, lever of effort, and lever of equal arms. Lever of ease: anvil, shears, and pulley. Lever of effort: chopsticks, tweezers, fishing rods, etc. Lever of equal arms: scale, see-saw, etc.

Scientific Principles:

1、关于杠杆：

1)、A hard rod, if it can rotate around a fixed point under the action of force, is called a lever.

2)、The elements of a lever: three points: the fulcrum, the point of application of the force, and the point of application of the resistance; two forces: the force and the resistance; and two arms: the force arm and the resistance arm.

3)、Lever balance condition: the force times the force arm equals the resistance times the resistance arm.

2、Catapult uses the principle of lever, where the power arm is shorter than the resistance arm, so it needs to

To throw a stone, you need a lot of strength. It is precisely because its lever arm is longer that it can throw the stone a long distance.