Question

When foam solution is created through a(n) _____, water is forced through a small opening that expands after it passes over the orifice where the foam concentrate is admitted to the fire stream.

Answer 1

The creation of firefighting foam involves the principle of entrainment, where water is propelled through a constricted area, combining with a foam concentrate due to a pressure drop to form an effective extinguishing agent.

Step-by-step explanation:

The student's question pertains to the process of creating a foam solution used for firefighting purposes, which involves the entrainment of a foam concentrate into the water stream. This process occurs when water is forced through a constricted area, known as an orifice, and then expands, resulting in a reduced pressure region that sucks in the foam concentrate. This is a similar principle to devices like the Bunsen burner, atomizers, and aspirators that use the increased speed of a fluid to generate low pressure areas that entrain another fluid. In the context of firefighting, the fluorinated solution created from the foam is able to spread effectively across the burning surface to extinguish large-scale fires involving organic liquids.