Final answer:
The question asks about converting x-ray exposure parameters when changing from single-phase to 3-phase equipment. It would require the radiographic technique conversion factor to accurately determine the mAs needed for similar image quality, which is not provided in the question. Therefore, a factual answer cannot be provided without the specific conversion factor.
Step-by-step explanation:
The subject question relates to the conversion of exposure parameters in radiography when switching from single-phase equipment to 3-phase, 12-pulse equipment. This involves understanding the properties and interaction of x-ray photons with different materials, particularly human tissue, and the aspects of radiation dosage in different scenarios. To determine the required mAs for a similar radiograph with 3-phase equipment, an understanding of the differences in power output and efficiency between single-phase and three-phase equipment is necessary. This kind of question typically involves radiographic technique conversion factors, which account for the increased efficiency of three-phase equipment over single-phase equipment. However, the question does not provide the direct conversion factor or enough information to calculate it. Because this factor can vary and the question doesn't specify it, the exact mAs value cannot be determined without making assumptions. According to typical conversion factors, three-phase, 12-pulse equipment may require approximately 40-50% less mAs than single-phase equipment to produce a similar image quality, but without the specific factor, an accurate calculation cannot be provided.