STEM Lessons for College Students

Optics – Lesson 35.0 – Interference and Coherent Sources – Two small stereo speakers A and B

*typo For part (a), I should have included 150 cm in my set of answers, and in part (b) I accidentally added 167 cm because I was thinking to correct part (a).

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Question from “University Physics with Modern Physics by Hugh D. Young and Roger A. Freedman, 14th Edition” via

Two small stereo speakers A and B that are 1.40 m apart are sending out sound of wavelength 34 cm in all directions and all in phase. A person at point P starts out equidistant from both speakers and walks so that he is always 1.50 m from speaker B (Fig. E35.1). For what values of x will the sound this person hears be (a) maximally reinforced, (b) cancelled? Limit your solution to the cases where x less than equal 1.50 m.

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