Final answer:
When an 8 inch PID is changed to a 16 inch PID with the same mA and kVp, the impulses required increase to 0.04 impulses, due to the inverse square law.
Step-by-step explanation:
The question relates to the principles of radiography, specifically the inverse square law in radiographic imaging. When doubling the distance of the PID (position indicating device) from 8 inches to 16 inches, while keeping the same milliampere (mA) and kilovoltage peak (kVp), the number of exposures, or impulses, needed to maintain image quality increases by a factor of four (due to the inverse square law).
With an original setting of 0.01 impulses at 8 inches, the number of impulses required at 16 inches is 0.04 impulses to maintain the same density on the radiograph, assuming no compensatory adjustments are made to either the mA or kVp settings.