Why do Trains Run on Rails?

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The wheels of a train run on rails. A flange in the inner side of each wheel holds it on to the rail. Both the wheel and rail, if made of steel, make a good combination because of less friction. A locomotive can pull ten times as much as a road vehicle of the same power. Rails are laid on steel or concrete sleepers. They also support the weight of the train. These are laid on a bed of stones packed on to the roadbed.

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