Final answer:
It is true that problems in a vehicle's suspension may lead to symptoms like swaying, heavy leaning, and continuous bouncing. A freight truck's trailer bouncing slowly likely indicates it is nearly empty because there is less mass to dampen the oscillations, as opposed to a heavily loaded trailer that would bounce less.
Step-by-step explanation:
It is true that 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. These symptoms suggest that the suspension components, like shock absorbers or springs, might be worn out or damaged, leading to poor vehicle handling and increased wear on other vehicle parts.
When observing a freight truck with a trailer bouncing up and down slowly on the highway, it is more likely that the trailer is nearly empty. Heavily loaded trailers have less tendency to bounce due to the additional weight dampening the oscillations. In contrast, an empty trailer has less mass to resist bouncing, and thus, the springiness of the suspension can lead to more pronounced, slower bounces. This is analogous to a car's bouncing behavior, which can be observed if you push down on the bumper and let go, causing the car to oscillate before coming to rest. The values of the period (T) and frequency (f) of these oscillations seem consistent with the behavior of a bouncing car, assuming the suspension's restoring force follows Hooke's law, which states that the force needed to extend or compress a spring by some distance is proportional to that distance.