Energy-absorbing bumper struts contain which of the following?

Energy-absorbing bumper struts are designed to absorb impact energy during a collision, thereby reducing the force transmitted to the vehicle's structure and occupants. The correct composition of these struts typically includes hydraulic fluid and compressed gas. Hydraulic fluid allows for the smooth transfer of forces and impacts, while the compressed gas, often nitrogen, is utilized to provide a cushioning effect and to help maintain the strut's performance during repeated impacts.

This combination works effectively to dissipate energy; the hydraulic fluid can create damping characteristics, while the compressed gas can adjust to the varying forces applied during an impact, offering resilience and reliability. Other combinations, such as air and water or gas and oil, do not provide the same level of performance and efficiency in energy absorption. Therefore, the configuration of hydraulic fluid and compressed gas is critical for optimal function in energy-absorbing bumper struts.