Duane-Hunt displacement law and Planck's "quantum of action"

Principle

X-ray spectra are recorded as a function of the anode voltage. The short wavelength limit of the bremsspectrum is used to determine the agreement with the Duane-Hunt displacement law, and to determine Planck's "quantum of action".

Tasks

1. Record the intensity of the X-rays emitted by the copper anode at various anode voltages as a function of the Bragg angle using an   LiF monocrystal.
2. Determine the short wavelength limit (= maximum energy) of the bremsspectrum for the spectra obtained in (1).
3. Use the results to verify the Duane-Hunt displacement law, and to determine Planck's "quantum of action".

Learning objectives

• X-ray tube
• Bremsstrahlung
• Characteristic X-ray radiation
• Energy levels
• Crystal structures
• Lattice constant
• Interference
• Bragg equation