If you double the mA while keeping kVp and exposure time constant, what happens to the x-ray beam?

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Multiple Choice

If you double the mA while keeping kVp and exposure time constant, what happens to the x-ray beam?

Milliampere controls how many x-ray photons the tube emits. Doubling the mA while keeping kVp and exposure time the same increases the tube current, so more electrons are produced and more x-ray photons are generated per second. With the exposure time fixed, that means the beam becomes more intense, i.e., the beam quantity increases. The energy of the photons—the beam quality—is set mainly by the peak kilovoltage; since kVp isn’t changed, the energy distribution stays the same, so beam quality does not change.

Milliampere controls how many x-ray photons the tube emits. Doubling the mA while keeping kVp and exposure time the same increases the tube current, so more electrons are produced and more x-ray photons are generated per second. With the exposure time fixed, that means the beam becomes more intense, i.e., the beam quantity increases. The energy of the photons—the beam quality—is set mainly by the peak kilovoltage; since kVp isn’t changed, the energy distribution stays the same, so beam quality does not change.

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