student extracurricular homework teacher xing balloon power car technology small production stem science laboratory 学生课外家庭作业 邢老师 气球动力车科技小制作 STEM科学实验室

For bulk custom orders from the factory, please contact: 1 5858 9 4 0 8 6

Product Name: C501 Balloon Truck

Model Number: C501
Size: 180*10*80 mm
Weight: 40g
Material: EVA + plastic components + hardware components + balloons
Packaging: 280 pcs
Box dimensions: 600*500*450mm

Scientific Insights:

Bombshells were already invented during the Song Dynasty, about eight to nine hundred years ago. Among them is a type called “qihua”. When gunpowder burns rapidly, the generated gas is ejected from the bottom of the qihua tube at a very high speed, causing the qihua tube itself to rise upward. The flight principle of modern rockets is similar—it also uses the recoil effect of high-speed ejected gas to give the rocket great velocity. What would happen if we use the force released by balloons to propel toy cars?

Experimental Objectives:

1, understand what recoil motion is and its characteristics
2. By understanding the effect of recoil, encourage children to love science.

Knowledge Treasure:

The phenomenon where an object ejects a large amount of liquid, gas, or objects in a certain direction at high speed, thereby acquiring reverse velocity, is called recoil motion.
Features: ① Interactions between objects occur suddenly, with short duration and strong effects.
②In the recoil phenomenon, the total external force acting on the system is generally not zero; if the internal forces far exceed the external forces during recoil motion, it can be assumed that momentum is conserved in the system during recoil motion.

In the problems of recoil motion, the velocity encountered sometimes is the relative velocity between interacting objects. This is where the relative velocity must be converted into absolute velocity before formulating the momentum conservation equation.

In recoil motion, variable-mass objects are also commonly encountered. For example, during the movement of a rocket, as fuel is consumed, its own mass continuously decreases. In such cases, both the rocket itself and the entire interaction process must be considered in the analysis.

Scientific Production:

1. Open the material package and locate the equipment required for the experiment.
2. Install the car in sequence as shown in the picture.
3. Fill the balloons with air and install them on the frame to begin the experiment

Knowledge Expansion:

Through analysis of examples, it is clear that recoil has both advantages and disadvantages. In addition to the recoil examples we mentioned earlier and their applications in real life, do any students have other examples of recoil applications? For jet planes and rockets we discussed, besides using the recoil principle, were other knowledge areas utilized? What is the difference between ancient Chinese rockets and modern rockets? Students can explore these questions by observing in daily life and through textbooks, and gain more understanding.
Movement and prevention of recoil: ①, Applications: irrigation sprinklers, counteracting turbines, jet aircraft, rockets, etc., all demonstrate the significant role of recoil. ②, Prevention: when shooting with a gun, the bullet moves forward while the barrel recoils backward. The recoil of the barrel affects the accuracy of the shot. Therefore, when using a rifle, the barrel should be pressed against the shoulder to reduce the impact of recoil.
Do you know? If a system does not experience any external forces, or the vector sum of all external forces acting on it is zero, then the total momentum of the system remains constant. This principle is known as the law of conservation of momentum. The law of conservation of momentum is one of the most important and universal conservation laws in nature. It applies to both macroscopic objects and microscopic particles; to both slow-moving and high-speed objects. It is an experimental law that can also be derived from Newton’s third law and the theorem of momentum.