Wavefront and diffraction problem clinic
≈ 48 minWavefront and diffraction problem clinic
Wave questions often require both a calculation and a diagram explanation. Begin by identifying the medium, wavelength, frequency and speed, then use v = fλ with compatible SI units. For diffraction, compare the gap width to wavelength and describe the outgoing wavefronts. When two coherent waves meet, constructive interference occurs where displacements reinforce and destructive interference where they cancel; use this only when the question includes overlapping waves. A careful answer distinguishes a claim from evidence: measured spacing can support wavelength, while a diagram's curved fronts support an inference about spreading.
Work it through
A water wave travels at 60 m s⁻¹ with frequency 10 Hz. λ = 60/10 = 6 m. A 6 m-wide gap will produce pronounced diffraction because gap and wavelength are comparable. A 60 m-wide gap produces less spreading. The calculation and the qualitative diagram should agree on the scale comparison.
Mastery target
Solve a wave calculation and use its result to justify a diffraction prediction or a labelled wavefront sketch without mixing frequency, wavelength and wave speed.
What is constructive interference?
Name the key physics term from Wavefront and diffraction problem clinic that best fits the explanation and visual model.
A wave travels at 60 m s⁻¹ and has frequency 10 Hz. What is its wavelength in m?
Which statement corrects a common misunderstanding in Wavefront and diffraction problem clinic?