← Back to topics

Machines & Transportation

🚗

How does a car work?

Fuel and air burn inside the engine. Moving pistons help turn the wheels.

⏱ 10–15 minute exploration🎓 Middle school level🛠 Mechanical engineering
Complete the quiz at the bottom for a surprise!

Your SimpleSci lab

Getting the moving parts ready…

🧑‍🔧

Someone had to figure this out

Mechanical engineer + chemical engineer

Mechanical engineers design moving parts such as pistons and crankshafts. Chemical engineers study how fuel and air burn so the engine can make power safely and efficiently.

Your turn: If you could improve one part, what would you change and why?

Find this interesting? Maybe you should be a mechanical or chemical engineer when you grow up!

1. Fuel becomes motion

A gasoline engine mixes fuel with air and burns it inside a cylinder. The hot gas expands and pushes a piston down. The piston turns a crankshaft, and that spinning motion eventually turns the wheels.

2. Gears match the engine to the wheels

The engine can spin much faster than the wheels. Gears help match engine speed to wheel speed. They can also increase torque, which means turning force, when the car needs to start or climb a hill.

3. Steering points the car

Turning the steering wheel changes the angle of the front wheels. That makes the car follow a curved path instead of going straight.

4. Brakes slow the car

Brake pads squeeze spinning discs connected to the wheels. Friction slows the car and turns some of its motion into heat.

5. Suspension handles bumps

Springs and shock absorbers let the wheels move over bumps without making the whole car bounce too much. This helps the tires stay in contact with the road.

6. Sensors help computers make adjustments

Sensors measure things like speed, temperature, and pressure. Small computers use those measurements to adjust systems such as the engine, brakes, and airbags.

Think like an engineer: Pick one part. What would happen if you made it lighter, stronger, or more efficient?

4 · Quiz

Does it make sense now?

Answer all five questions. Your best score is saved on this device.

1. What does the crankshaft do?

2. What does the spark plug do?

3. What enters the cylinder during the intake step?

4. What happens during the power step?

5. In this model, what happens when you press the gas pedal farther?

One big idea. Now it makes sense.

Ready to explain it to someone else? Mark this exploration complete, then follow your curiosity to the next one.

What will you figure out next?