When you were young, did you ever play with toy trains? People who build model railroads use ratios to make their trains look realistic. Many parks and amusement parks also feature steam engines built with ratios. These little trains are scaled-down models of real locomotives.
Scaling the Model
To build a good model railway, it's not enough to pay attention to the ratios of the little trains to real engines. Builders also make sure that houses, trees, people, and animals are likewise scaled down. Otherwise, the proportions of the trains wouldn't match the proportions of their environment. The model railway would look ridiculous!
One of the most famous model railway exhibits in America is housed in the Museum of Science and Industry in Chicago, pictured above. The museum opened its first model railroad exhibit in 1940. In 2002, the museum temporarily closed the original exhibit in order to expand and modernize it. To create the new exhibit, 40 people worked for an entire year. They designed the exhibit using a Computer-Aided Drafting (CAD) program that allowed them to easily compute ratios and heights. The designers were so accurate that they included real people in the models. The miniature people on the Red Line train platform represent the actual people who stood on the real-life platform at 1:56 on April 3, 2002.
Hobbyists aren't the only people who create scale models. Builders and architects use scale models to help them design houses.
How do scale models help builders?