When applying the 2 kVp per cm rule, you are adjusting

When applying the 2 kVp per cm rule, you are adjusting

• A. Kilovoltage (kVp) only
• B. mA only
• C. Exposure time only
• D. Distance only

Answer: (A)

The main idea is using kilovoltage to compensate for changes in how much the body part attenuates the X-ray beam. When a part is thicker, it attenuates more; increasing kVp by about 2 per additional centimeter raises the beam’s penetrating power so the image receptor still receives enough exposure. This rule specifically targets changing kilovoltage, not adjusting the tube current (mA), exposure time, or distance. Adjusting mA or time would change the number of photons and the overall exposure, while distance changes intensity via the inverse-square law; but the 2 kVp per cm guideline is about tweaking kVp to maintain consistent image brightness and adequate penetration.

The main idea is using kilovoltage to compensate for changes in how much the body part attenuates the X-ray beam. When a part is thicker, it attenuates more; increasing kVp by about 2 per additional centimeter raises the beam’s penetrating power so the image receptor still receives enough exposure. This rule specifically targets changing kilovoltage, not adjusting the tube current (mA), exposure time, or distance. Adjusting mA or time would change the number of photons and the overall exposure, while distance changes intensity via the inverse-square law; but the 2 kVp per cm guideline is about tweaking kVp to maintain consistent image brightness and adequate penetration.