Mother Xiong’s three children have become drivers when they grow up. Xiong Da drove trains, Xiong Er Er drove trolleybuses, and Xiong Xiaoxiao drove cars.
One day, they met together and compared cars with each other. Xiong Xiao Novel: “It’s better to have a big train, big and long-distance running fast, more mighty and more chic!” Xiong shook his head greatly, and said: “You don’t know, my car is very unfree, one day I can only run on the railway tonight. How unfree it is. If you are not free, you are not chic. I think the second trolleybus is more free than my train, and the small car is more free, so you guys are chic Ah!” Xiong Er’er waved his hand and said, “I don’t actually have any freedom. Have you all seen the two “braids” on my car? It’s like two ropes binding me and giving it to me. Space is so limited.” Xiong Xiaoxiao listened to them and laughed: “So, I am the most free and unrestrained. Then, you guys should think of a solution.” “Yes,” Xiong Da said, “I I think it will be fine if my train is separated from those two rails.” “Yes,” Xiong Er’er said, “I think my trolleybus is separated from those two’braids’.”
As a result, Xiong greatly drove the train off the tracks, and Xiong Er Er took off the “braid” of the trolleybus. However, the train was stuck in the mud and couldn’t move. The trolleybus “lays down” on the spot and does not move forward.
“What’s going on here?” They were consulting again and flipping through the book, and finally figured it out. Xiong Da said: “Train runs on railways, cars run on highways, ships run on waterways. What kind of car or road, trains do not have the freedom to run on roads. Even if this kind of freedom is given, it is useless. It seems that some freedoms are not free. “Pursuing.” Xiong Erer said: “It’s quite right. Under certain conditions, restraint is power. This time I understand that the two’braids’ of trolleybuses provide power and are indispensable.” Xiong Xiao Xiao blinked his eyes and asked, “Why?” Xiong Er’er replied: “Because the power of a tram is electricity, and electricity must flow into the engine of the tram through a’braid’. This current is the same as water flow. Two “braids” are installed on the tram, which means that the current flows from one “braid” into the engine of the tram to turn the engine, and then the current flows from the other “braid” back to the power plant. And if the “braid” is separated , Even if it is one, the current will be interrupted immediately, and the tram will naturally stop moving.”
Xiong Da blushed and said, “What will we think of in the future, we must conform to knowledge, and we must not act blindly!” Xiong Erer and Xiong Xiaoxiao nodded, and at the same time they worked with Xiong Da to lift the train onto the rails. Connect the “braid” of the trolleybus. The car is running, the trolleybus is running, and the train is running…