Can you imagine that two small stones can collide to generate electricity and light up a small lamp? Can you imagine that knocking on the door with your hand can power the LED board and illuminate the book? Can you imagine that the 28-watt fluorescent tube lamp can be lit up when you walk with it in your hand[? It turns out that generating electricity is simple. The energy generated by gently rubbing the plastic plate can light up at least a one-watt bulb, and even charge the mobile phone. The simple generator is made into a cylindrical type, which can efficiently collect wind energy under low wind speeds and easily light up ten one-watt bulbs.We know that the motion of objects in the universe is eternal. As long as there is motion, there will be interactions. I have found that electromagnetic energy will be generated when matter collides with each other，including macroscopic objects collisions and microscopic particles collisions. Thus I put forward "the Collision Electro-Magnetic Theory" . In addition, base on these discoveries, I found that rotating a closed circuit coil in a changing electric or electrostatic field could also generate an induced current and induced electromotive force in the coil. Which I call it Electra-electric induction (EEI). Both Maxwell displacement current and the electra-electric induced current we found are generated by the changing electric field. They are two forms of changing electric field. One existed in space. The other existed and flow in the conductor. The Maxwell displacement current is collected by the coil and flows, that is induced current.All these findings will be of great significance both in theory and in applications. Just like the invention of electromagnetic induction by Faraday in 1831, it is a milestone progression.Professor Xia CAO has made a series of discoveries that have gone entirely from 0 to 1, overturning traditional perceptions. Just like opening a door, it will have an immeasurable impact on physics, astronomy, new energy, nuclear energy, military and other fields. It will drive revolutionary anddisruptive progress in related industries and the global economy.