Final answer:
Bob should wear a helmet while riding the Costa Rican Jungle Slide to protect his head from the effects of inertia, which will cause his head to continue moving if his body suddenly stops.
Step-by-step explanation:
Inertia is the property of a body to resist changes in its motion, meaning objects tend to keep doing what they're already doing - either staying still or moving at a constant velocity. When Bob rides the Costa Rican Jungle Slide, he is in motion along with the slide. If he were to suddenly stop but didn't have a helmet, his body might stop, but because of inertia, his head would want to continue moving. Wearing a helmet provides important protection for his head in such a scenario.
The inertia of an object, which is related to its mass, makes it difficult to change that object's state of motion. Since Bob’s brain has mass, in the event of an abrupt halt, his brain would keep moving due to inertia, potentially causing injury if he is not wearing a helmet. A helmet adds a layer of protection, absorbing some of the impact, and helping to prevent or reduce head injuries.