#3244: Pullback Drive

XKCD comic, described below.
Transcript

[Hairy and Cueball are standing to the right of a medium-size car. Hairy has raised one hand slightly to point to the car.]

Hairy: You won't have to worry about gas prices or electricity prices with our new pullback drive model.

Hairy: At the factory, we put the car on the ground and tow it all the way backward until it starts clicking.

Hairy: To drive forward, you just release the brake and it goes.


(Sourced from explainxkcd.com)

"How does the spring not run out almost immediately?" "We pull it back REALLY far."

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