Final answer:
The driver is usually legally responsible for ensuring that all passengers under the age of 18 are wearing seat belts, with penalties for non-compliance. Seat belts are critical for safety, preventing injuries, and reducing societal medical costs.
Step-by-step explanation:
In terms of legal responsibility for ensuring passengers are wearing seat belts, the answer will vary depending on the jurisdiction. However, commonly, the driver is responsible for passengers under a certain age. In many places, the age is set at 18, where drivers could be fined if passengers under this age are not properly belted in.
It is important to note the ramifications of not wearing a seat belt. In a car crash scenario, a seat belt can greatly reduce the risk of injury. For instance, using force calculations involving speed and time, we can determine the force exerted by the seat belt on a passenger to halt them suddenly, illustrating the seat belt's role in mitigating harm.
Seat belt laws are enacted not only to protect individuals but also to prevent unnecessary strain on medical services and societal resources that may result from injuries in car accidents. This ensures a safer environment for both the individuals and society as a whole.