An increase in the kilovoltage applied to the x-ray tube increases the?

Increasing the kilovoltage (kV) applied to the x-ray tube primarily affects the exposure rate, which is the amount of x-ray radiation produced per unit time. A higher kV results in increased energy of the x-ray photons generated. This leads to a greater quantity of x-rays being produced and an increase in the overall intensity of the x-ray beam.

As the energy of the x-ray photons increases with higher kV, the beam has a higher penetrating ability, allowing for more x-rays to reach the image receptor rather than being absorbed by the patient's tissues. This increase in penetration also contributes to a higher exposure rate since more photons are able to pass through the anatomy and contribute to the final image formation.

In contrast, a higher kilovoltage does not increase the x-ray wavelength, as wavelength decreases with increasing energy in the context of electromagnetic radiation. Likewise, it does not directly lead to increased patient absorption; rather, it typically results in less absorption by the patient’s tissue due to the more penetrating nature of the x-rays. Thus, the increase in exposure rate reflects the primary impact of raising the kilovoltage.