Concepts Of Physics MCQ Edition [Volume 2]PhysicsX-rays
An X-ray beam emerging from an X-ray tube
Options
- Acontains all wavelengths shorter than a specific maximum wavelength
- Bis strictly monochromatic
- Ccontains all wavelengths bounded between a minimum and a maximum wavelength
- Dcontains all wavelengths longer than a specific minimum wavelength
Correct answer
D. contains all wavelengths longer than a specific minimum wavelength
Step-by-step solution
The X-ray beam emerging from an X-ray tube consists of continuous X-rays (Bremsstrahlung) and characteristic X-rays. The continuous X-ray spectrum has a sharp lower limit for the wavelength, known as the cut-off wavelength or minimum wavelength, given by _ min = hc eV , where V is the accelerating voltage across the tube. There is no theoretical upper limit to the wavelength of the continuous X-rays produced, meaning the spectrum extends to longer wavelengths with decreasing intensity. Therefore, the X-ray beam con