X-Ray Certification Exposure Factors 2

Question 1

A radiograph appears too light (underexposed). Which adjustment would most directly increase radiographic density?

Accepted Answer

Increase mAs by 50%

Answer

mAs directly controls the quantity of x-rays produced, so increasing it raises radiographic density.

Question 2

Which of the following best describes the effect of increasing kVp on radiographic contrast?

Accepted Answer

Contrast decreases because more scattered radiation is produced

Answer

Higher kVp produces more Compton scatter, which adds noise and reduces radiographic contrast.

Question 3

When doubling the SID, how must mAs be adjusted to maintain the same receptor exposure?

Accepted Answer

Quadruple the mAs

Answer

The inverse square law requires mAs to be quadrupled when SID doubles to compensate for the fourfold reduction in intensity.

Question 4

A patient's arm is imaged at 60 kVp / 5 mAs. To apply the 15% kVp rule and maintain density, what should the new technique be?

Accepted Answer

69 kVp / 2.5 mAs

Answer

Adding 15% to kVp (≈69 kVp) doubles receptor exposure, so mAs must be halved to 2.5 mAs to maintain density.

Question 5

Which exposure factor primarily determines the quality (penetrating power) of the x-ray beam?

Accepted Answer

kVp

Answer

kVp sets the peak energy of the x-ray beam, which determines its penetrating power.

X-Ray Certification Practice Test