Final answer:
When changing from a 16-inch PID to an 8-inch PID while keeping the same mA and kVp, the impulses would be 40.
Step-by-step explanation:
To find the impulses when changing from a 16-inch PID to an 8-inch PID, we can use the formula:
Impulses1 x Distance1 = Impulses2 x Distance2
Given that Impulses1 = 20 impulses, Distance1 = 16 inches, Distance2 = 8 inches, we can substitute the values into the formula:
20 impulses x 16 inches = Impulses2 x 8 inches
Solving for Impulses2, we get:
Impulses2 = 40 impulses.