Final answer:
A vehicle that sways or bounces continuously likely has a problem with its suspension system. An empty trailer on a highway will bounce more slowly due to less inertia compared to a loaded one, and the car's bouncing can be understood as a sine wave motion.
Step-by-step explanation:
If a vehicle sways freely, leans heavily to one side during a turn or seems to bounce continuously, there may be a problem with the suspension system.
When a freight truck with a trailer on a highway has a bouncing trailer, the slow up and down motion observed can give us information about its load. If the trailer is bouncing up and down slowly, it is more likely to be nearly empty. The reason is that a heavily loaded trailer would have a dampened oscillation due to the increased mass, which adds inertia and results in a less bouncy ride. Conversely, a nearly empty trailer does not have that much inertia, allowing for longer, slower bounces as there is less mass to resist the oscillations initiated by bumps or irregularities in the road surface.
The observation that a bouncing car's motion can be likened to a sine wave due to the Hooke's law characteristics of the suspension is crucial to understanding the behavior of the system. When you push down on one end of a car and let go, you can see the oscillations described by the values of T (period) and f (frequency), reflecting the motion of the bouncing car.