Answer: Δλ = (h/m e c)(1 - cosθ) (Compton formula).
- A Δλ = (h/m<sub>e</sub> c)(1 - cosθ) (Compton formula)
- B Δλ = hν, dimensionally an energy rather than a wavelength shift
- C Δλ = 0 (no change), as in purely elastic Thomson scattering
- D Δλ = hf/c, dimensionally a momentum rather than a wavelength shift
Correct answer: A. Δλ = (h/m<sub>e</sub> c)(1 - cosθ) (Compton formula)
Explanation: Compton shift: Δλ = (h/m<sub>e</sub> c)(1 - cosθ) where θ is the scattering angle and h/m<sub>e</sub> c = 2.43 pm is the Compton wavelength. This confirms the particle nature of X-rays.
In an electromagnetic wave, the oscillating electric field (E) and magnetic field (B) are perpendicular to each other and to the direction the wave travels - a purely transverse wave that needs no medium, unlike sound.
Concept context
Maxwell's equations, EM spectrum, properties, and applications of each band.