Skip to content

Transportation • Short read + interactive lab

How does an electric vehicle work?

Press the accelerator and see how electricity turns a motor and moves a car.

Finish the quiz for an adventure!

The big idea

Electricity goes in. The motor spins.

Pressing the accelerator tells the car how much power you want. The battery sends electricity to an inverter, which controls the electricity going to the motor. Magnetic forces inside the motor make it spin. Gears connect that spinning motion to the wheels.

Your SimpleSci lab

Getting the moving parts ready…

🧑‍🔧

Someone had to figure this out

Electrical + mechanical engineer

EV engineers design batteries, motors, electronics, gears, cooling systems, and safety systems that all work together.

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

Find this interesting? Maybe you should be an electrical or mechanical engineer when you grow up!

Start here · The simple story

Electricity gives the wheels a turn

Read on your own or with a grown-up. Try the model above as you read.

  • The battery stores energy. It sends electricity to a motor.
  • Magnets can push or pull. Magnetic pushes and pulls make the moving part inside the motor spin.
  • An inverter controls the electricity sent to the motor. Gears carry the motor’s turn to the wheels.
  • The drive pedal tells the car how much power the driver wants.
  • When the car slows, the wheels can turn the motor to make electricity. Some energy goes back into the battery.
  • Not all that energy can be saved. Some becomes heat.

Following the energy

You press the pedal. What gets the message?

The accelerator tells the car’s electronics how much drive power you are asking for. The battery stores energy chemically and supplies electrical energy. An inverter changes and controls the electricity going to the motor. Magnetic forces spin the motor; gears carry that rotation to the wheels.

  1. BatteryStores and supplies energy.
  2. InverterControls electricity for the motor.
  3. MotorTurns with magnetic forces.
  4. Gears → wheelsCarry the turn to the road.

A charged battery alone cannot decide how fast to drive. The electronics coordinate the flow of energy in response to the pedal and the car’s operating limits.

Motion from magnetism

How can a motor turn without burning anything?

You may have felt two magnets pull together or push apart. Inside an electric motor, current creates magnetic fields. Controlled changes in those fields make the rotating part—the rotor—keep turning.

A gasoline engine burns fuel and moves pistons up and down. An EV’s drive motor uses magnetic forces to produce rotation directly. It can make strong turning force, or torque, even at low speed.

Matching the wheels

If the motor spins so fast, why don’t the wheels?

A reduction gear lets the motor make several turns for each turn at the wheels. This gives a useful wheel speed and more turning force, much like choosing a lower gear on a bicycle to get moving.

The gear does not add energy. It trades rotational speed for torque, helping a fast-spinning motor do the slower, stronger turning job the wheels need.

Energy on the return trip

How can slowing down help charge the battery?

During regenerative braking, the moving wheels drive the motor. It works as a generator, converting some energy of motion into electrical energy that can return to the battery. Taking energy out of the car’s motion slows it down.

  1. Moving wheelsDrive the motor.
  2. Motor as generatorConverts motion into electricity.
  3. BatteryStores some recovered energy.

This is energy recovery, not free energy. Some energy becomes heat, and the battery cannot always accept all the available power. EVs still use friction brakes when needed.

A short history of electric cars

Electric cars are older than you might think.

An electric car on an old-fashioned street is not a time-travel mistake. Battery-powered vehicles were already rolling around more than a century ago. Their history has a surprising comeback.

  1. Around 1890 · An electric wagonWilliam Morrison built a six-passenger electric vehicle in Iowa. It could reach about 14 miles per hour. It was no racing machine, but it helped people imagine driving on battery power.
  2. Early 1900s · Quiet cars, tough competitionElectric cars appealed to city drivers because they were quiet and easy to operate. But cheaper gasoline cars, more filling stations, and limited access to electricity outside cities helped gasoline take the lead.
  3. 2000s onward · An old idea gets another chanceImproved batteries and renewed interest in using less gasoline helped electric cars return to the spotlight. Engineers worked on driving range, cost, and places to charge.

The idea stayed familiar: a battery supplies energy and a motor turns the wheels. The challenge was making the whole system useful for more drivers. Sometimes invention means giving an old idea better tools.

4 · Quiz

Does it make sense now?

Answer all 10 questions to unlock your adventure. Use the hints to try again. Returning starts a fresh quiz and locks the adventure; earned upgrades stay saved.

1. Which part stores energy for the electric car?

2. What makes the electric motor turn?

3. What does the inverter help control?

4. When the car slows, where can some energy go?

5. What carries the motor’s turn to the wheels?

6. How does the moving part inside the motor move?

7. What can magnets do to each other?

8. Does slowing down save all the car’s energy?

9. What does the drive pedal tell the car?

10. What does the battery send to the motor?

One big idea. Now make it yours.

Answer all 10 quiz questions and check your answers to save this lesson as completed. Aim for 10/10 to earn Mastered.

Try a family challenge on your next visit →
View my progress →

Your next discovery