What is the difference between an inertia car and a pull-back car?

[Lorenzo]

Inertia cars and pull-back cars differ in terms of construction, working principle, and direction of movement. Construction differences: An inertia car has a relatively large and heavy flywheel inside, requiring it to be pushed forward before being released to move forward; a pull-back car has a spring inside, requiring it to be pushed backward before being released to move forward. Principle differences: Inertia car principle: The 'flywheel' mechanism in an inertia car demonstrates its mechanical principle. When the rear wheels move backward or forward, they drive the flywheel to rotate rapidly in the opposite direction, storing rotational kinetic energy like a spring. When released, this energy is discharged, causing the car to move forward due to inertia for a certain distance. Pull-back car principle: The 'axle' connected to the rear wheels of a pull-back car is fixed to the internal gear of the pull-back mechanism. When the car is pulled backward, the rear wheels rotate in the same direction, transferring motion through the 'axle' to the gears, which then drive the pull-back mechanism to propel the car forward. Direction of movement differences: Inertia cars can move both forward and backward due to the 'flywheel' mechanism. Pull-back cars can only move in a fixed, single direction.