Answer:
The answer to your question is Friction
Explanation:
As is mentioned in the question, Betsy held on to the sides of the slide the whole way down, that means that her hands were rubbing the slide and this process causes a force called friction. And Friction is perceived as heat.
The definition of friction is: Friction is the resistance to motion of one object moving relative to another.
In your question her hands create a resistance to motion.
