In a centrifugal compressor, what is transformed into potential energy?

In a centrifugal compressor, low-pressure, high-velocity vapor is transformed into potential energy. This transformation occurs through the compressor's design, which utilizes a rotating impeller to accelerate the vapor. As the vapor enters the compressor, it is at low pressure and at high velocity. The action of the impeller increases the kinetic energy of the vapor and pushes it outward towards the diffuser.

In the diffuser, the high-velocity vapor slows down, resulting in an increase in pressure. This process effectively converts the kinetic energy of the vapor into potential energy, which is represented by increased pressure. The potential energy gained by the vapor is essential for the compressor's operation, as it allows the vapor to be efficiently moved into the next stage of the refrigeration cycle or process.

Other options, such as high-pressure vapor, liquid refrigerant, and heat energy, do not represent the direct transformation occurring in a centrifugal compressor. High-pressure vapor is generally not the input for these compressors, and liquid refrigerant typically requires different handling. Additionally, heat energy relates to temperature rather than pressure changes necessary for the compressor's operation.