What do the people who build roller coasters do if the cars don't have enough speed to make it up the hill?

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We can't all be racing drivers or astronauts. Not everyone can dive to the bottom of the sea or climb up Mount Everest. But we can all go on rollercoasters and see what it feels like to push ourselves to the limit. You might think rollercoasters are all about testing your body, but your mind's being worked out too: the mental psychology of fear makes the whole physical experience so much more exciting. Let's take a closer look at the science of extreme rides!

Photo: Rollercoasters turn physics into fun! Photo

Roller coasters run on kinetic energy, so I would think that the tracks would propel them before they go up a hill, and then trasnferred to kinetic energy,

Explanation:

but don’t use my answer, the first time I used a roller coaster, we got stuck up the top for almost half an hour, and that’s how I got my fear of heights.

not sure how to answer your question sorry