Question

If 85 kVp, 400 mA, and ⅛ s were used for a particular exposure using single-phase equipment, which of the following milliamperage or time values would be required, all other factors being constant, to produce a similar density using three-phase, 12-pulse equipment?

1. 200 mA
2. 600 mA
3. 0.125 s
4. 0.25 s
Answer:
200 mA

Answer 1

To produce a similar density using three-phase, 12-pulse equipment, a milliamperage value of 200 mA is required.

Step-by-step explanation:

In single-phase equipment, the milliamperage (mA) or time values needed to produce a similar density using three-phase, 12-pulse equipment can be calculated using the formula:

mA2 = mA1 x (kVp2/kVp1) x (time2/time1)

where mA2 is the milliamperage of the new equipment, mA1 is the milliamperage of the old equipment, kVp2 is the kilovoltage peak of the new equipment, kVp1 is the kilovoltage peak of the old equipment, time2 is the exposure time of the new equipment, and time1 is the exposure time of the old equipment.

In this case, the kVp and time values are constant, so we only need to find the new milliamperage value. By plugging in the given values (85 kVp, 400 mA, and ⅛ s), and solving for mA2, we get:

mA2 = 400 x (85/85) x (⅛/⅛) = 400 mA

Therefore, the milliamperage value required to produce a similar density using three-phase, 12-pulse equipment is 200 mA.