Why do trains go?
For grown-ups: the science
A motor powered by electricity spins the wheels, and the wheels push back against the tracks to make it go.
Most trains draw electricity from overhead wires, a third rail, or onboard batteries and generators, using it to power a motor that turns the wheels. Static friction between the wheels and rails lets the wheels push the rail backward, so the rail pushes the train forward in return. Diesel trains burn fuel to run an engine or generator instead, but the push between wheels and rails works the same way.
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Transcript
A train rides along long, long tracks. How does it get moving so fast?
Under the train, there are round wheels and a motor that runs on electricity. The motor spins the wheels round and round.
The spinning wheels push against the tracks, pushing backward. Then the tracks push back, and the train moves forward.
On top of the train, there's a tool that catches electricity from a wire above. That electricity keeps the motor running the whole time.
Electricity spins the wheels, and the wheels push the tracks, so the train can go.