From light powered by knocking on the door to the investigation on three types of collision

Highlights: • 1350 LEDs can be easily lit up when you knock hard on a door with your hands. • Electromagnetic field is generated in the collision process of two objects. • The electromagnetic fields generated in three types of collisions have been compared. • A simplest power generation system, positioning system and path tracking system have been designed. • This work will improve the understanding about collision theory in classical physics. Can you imagine that when you knock hard on a door with your hands, 1350 LED lights can be lit up! Science and technologies are all constantly being developed and improved in practice. Any scientific theory is not ultimate and absolutely precise. In this paper, we studied the traditional macroscopic collision theory based on the latest research findings: electromagnetic field is generated when two objects collide with each other owing to the contact-electrification between the two. Three types of collision phenomena: elastic collision, inelastic collision, and ideal inelastic collision were investigated in detail. We found that electromagnetic field was produced during all three types of collisions, which means mechanical energy is converted into electromagnetic energy during any collision process of two objects. Under the same condition, the quantity of electric energy produced by elastic collision is greater than that of inelastic collision, and greater than that of ideal inelastic collision. Different from the conversion of mechanical energy into internal energy in the process of collision, the change of mechanical energy into electromagnetic energy in the process of collision will directly affect the law of conservation of energy and momentum in the whole collision system. The electric power generated in collision can not only be used for lighting, but also it can be used for positioning and tracking. This is completely new discoveries, which will provide new explanations and new ideas and will have a profound and an inestimable impact on some related scientific research fields, including physics and new energy.