Final answer:
Hermetic compressors in refrigeration and air conditioning systems typically operate at speeds ranging from 1,750 to 3,600 rpm.
Step-by-step explanation:
The student has asked about the rotational speed at which a hermetic compressor normally operates. While the question does not provide a specific answer, we can infer that the context is related to the mechanics of how various engines and motors operate in terms of rotational speed or angular velocity.
Typically, a hermetic compressor found in refrigeration and air conditioning systems may operate around 1,750 to 3,600 rpm, depending on the design and application.
However, without more context, it is not possible to provide an exact number. For refrigeration systems, the Coefficient of Performance (COPref) ranging from 2 to 6 indicates efficiency relative to idealized systems.
As for the turbofan jet engine example provided, it describes an acceleration to 40 rev/s, which can be used to understand the concept of angular acceleration but is not directly related to hermetic compressors.
The specific speed can vary based on the design and application. The question's context is related to the mechanics of engines and motors regarding rotational speed.