Rail vehicle resistance

High school (ages 12+)
Transportation

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/rail-vehicle-resistance

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the dominant resistance factor at high speeds?Aerodynamic drag, which increases with the square of velocity
2. What is the key components of rolling resistance?Deformation of wheels and rails, and internal friction
3. Why does a train need more power at higher speeds?Because aerodynamic drag grows with the square of the train's speed, so the train has to push harder to keep going.
4. How do train designers make trains use less energy?They shape trains to be smooth and narrow, use light materials, and choose good wheel and rail materials to reduce friction.

Aerodynamic Drag Coefficient (Cd): A dimensionless number that quantifies the drag or resistance of an object in a fluid environment.
Rolling Resistance Coefficient: A factor representing the resistance encountered when a body rolls over a surface.
Tractive Effort: The force exerted by a locomotive to move a train, equal to resistance at constant speed.