Which of the following is considered a characteristic of a rotary compressor?

A rotary compressor is characterized by its use of mechanisms such as vanes or screws to compress the gas within. This design allows for continuous operation and is efficient for a range of applications, including refrigeration and air conditioning. The rotary motion creates a uniform airflow and minimizes vibrations, making it suitable for situations where space and noise are considerations.

While some compressors may utilize pistons and cylinders, this is not a defining feature of rotary compressors, as those typically fall under reciprocating types. Similarly, the assertion that rotary compressors are solely used for vapor compression is not accurate since some can also handle gas mixtures and be part of various thermodynamic processes. Lastly, rotary compressors can operate at both low and high speeds, depending on their design and application, rather than being limited to low speeds.