HCI 10 Superposition Lecture Notes

Hwa Chong Institution (College) H2 Physics C1 2023 1 Chapter 10 SUPERPOSITION Interference pattern produced by two sources placed at different distances apart and of different wavelengths. Taken from www.arthistoryclub.com Playlist of Lecture Example Solutions and Others available at https://youtube.com/playlist?list=PL_b5cjrUKDlbeRspxU7s_UswuIC_U1VMJ

Hwa Chong Institution (College) H2 Physics C1 2023 2 Syllabus 9749 Content • Principle of Superposition • Stationary Waves • Diffraction • Two-source interference • Single slit and multiple slit diffraction Learning Outcomes Candidates should be able to: (a) explain and use the principle of superposition in simple applications. (b) show an understanding of the terms: interference, coherence, phase difference and path difference. (c) show an understanding of experiments which demonstrate stationary waves using microwaves, stretched strings and air columns. (d) explain the formation of a stationary wave using a graphical method, and identify nodes and antinodes. (e) explain the meaning of the term diffraction. (f) show an understanding of experiments which demonstrate diffraction including the diffraction of water waves in a ripple tank with both a wide gap and a narrow gap. (g) show an understanding of experiments which demonstrate two-source interference using water waves, sound waves, light waves and microwaves. (h) show an understanding of the conditions required for two-source interference fringes to be observed. (i) recall and solve problems using the equations  = a x / D for double slit interference. (j) recall and use the equation sin 𝜃 = 𝜆/𝑏 to locate the position of the first minima for single slit diffraction. (k) recall and use the Rayleigh criterion 𝜃 ≈ 𝜆/𝑏 for the resolving power of a single aperture. (l) recall and use the equation d sin  = n  to locate the positions of the principal maxima produced by a diffraction grating. (m) describe the use of a diffraction grating to determine the wavelength of light. (the structure and use of a spectrometer are not required.)

Hwa Chong Institution (College) H2 Physics C1 2023 3 Contents Syllabus 9749…………………………………………………………………………………………….2 Content 2 Learning Outcomes 2 10.1 – Introduction ……………………………………………………………………………………. 4 10.2 – Principle of Superposition ………………………………………………………………….. 4 10.3 – Interference ……………………………………………………………………………………. 5 10.4 – Interference of Two Wave Sources ………………………………………………………... 7 10.4.1 – Interference of Waves from Two Sources that are in Phase 7 10.4.2 – Accounting for Phase Difference at the Sources 11 Tutorial 10A: Superposition and Interference …………………………………………………... 13 10.5 – Interference of Light Waves: Young’s Double Slit Experiment ……………………… 17 10.6 – Diffraction Grating ………………………………………………………