513_Physics ProblemsTechnical Physics

513_Physics ProblemsTechnical Physics - Chapter 17 515...

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Chapter 17 515 between your sound impulse reaching each riser and the next. Whatever its material, each will reflect much of the sound that reaches it. The reflected wave sounds very different from the sharp pop you made. If there are twenty rows of seats, you hear from the bleachers a tone with twenty crests, each separated from the next in time by 206 340 0004 . . m ms s af bg = . This is the extra time for it to cross the width of one seat twice, once as an incident pulse and once again after its reflection. Thus, you hear a sound of definite pitch, with period about 0.004 s, frequency 1 00035 300 . ~ s Hz wavelength λ == = v f 340 300 12 10 0 s m m .~ and duration 20 0 004 10 1 s s . P17.52 (a) = v f 343 1480 0232 1 s m . (b) β L N M M O Q P P 81 0 10 10 12 .l o g dB dB Wm 2 I Iv s s I v = × = × −− 10 10 10 1 26 10 1 2 2 2 1 26 10 120 343 4 841 10 12 8 10 3 90 4 2 2 2 4 21 2 8 kg m m s s m 22 2 2 3 ej .. max max . . . . ρω π (c) ′= v f 343 1397 0246 1 s m . λλ λ =′ −= 13 8 . mm P17.53 Since cos sin 1 θθ += , sin cos 1 2 (each sign applying half the time) ∆∆ PP k xt v s k =−
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This note was uploaded on 12/14/2011 for the course PHY 203 taught by Professor Staff during the Fall '11 term at Indiana State University .

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