What are the advantages and disadvantages of trains?

Advantages: low price, safety, little weather influence and wide distribution.

Disadvantages: the environment is noisy, the speed is slow, and some places can't go, sometimes it's crowded, or it's hard to get a ticket.

Trains are a typical example of human transportation using fossil energy. 1804, the world's first steam locomotive was built by British mining technician Drivesk using Watt's steam engine, with a speed of 5 to 6 kilometers per hour. Because coal or firewood was used as fuel at that time, people called it "train" and it has been used ever since.

Extended data:

Train operation principle:

The bogie of the train is stuck on the track and runs along it. When turning, the bogie rotates to keep the train running along the track. The outer rail is higher than the inner rail when turning.

The original trains were drawn by ropes or horses. By the19th century, most trains were pulled by steam locomotives. After the 1940s, steam locomotives were gradually replaced by diesel locomotives which were cleaner and needed less labor, and then electric locomotives and multiple units appeared.

The initial investment of electrified railway is large, but the operating cost per mile is the lowest. Therefore, only high-flow lines are suitable for electrification. Electrified trains may use overhead cables or the third rail to obtain electricity.

The efficiency of computer headstock divided by unit kilowatt (kW) power and tractable weight metric Tons (ton) is called tractive capacity ratio. The efficiency of steam locomotive is the lowest, followed by diesel locomotive (electric transmission ratio is high), and electric locomotive or electric locomotive is much more economical. Because there is no need to consume extra kinetic energy to pull the engine that generates power.