1Would the amplitude on this graph mostlikely be…a) Velocity amplitudeb) Displacement amplitudec) Pressure amplituded) Wavelength amplitudee) None of the above5.1.1Position (m)Time (s)Which amplitude have we been mostconcerned with when studying music so far?(why?)5.1.2Which sound is stronger?a) The one on the leftb) The one on the rightc) They are the same strengthd) You can’t tellOver Pressure (N/m2)Time(s)Time(s)Over Pressure (N/m2)5.1.3Looking at the following two graphswhat can you say about the energycarried by the wave?a)The energy is larger in I.b)The energy is larger in II.c)The energy is the same in bothd)You can’t tell anything about theenergy from these graphse)What does energy have to dowith music?Over Pressure (N/m2)Time (s)Over Pressure (N/m2)Time (s)I.II.5.1.4If you do overall positive work on asystem, what happens to the totalenergy of that system?a) Energy increasesb) Energy decreasesc) Energy is conserved, it does notchange.d) ??2CT 5.1x.1You pull a mass on a spring 1 cm andlet it go. Suppose it has 2 Joules (2 J)of energy.If you now pull it 10 cm and let it go,how much energy does it have?A) 2 JB) 10 JC) 20 JD) 100 JE) 200 J A B C D The above pictures represent wave frontsof a sound wave emitted from some source.Which source is moving at the speed ofsound?5.1.6A light bulb has a power of 100 J/s (alsocalled 100 Watts). After being on for 2seconds how much energy has the bulbreleased?a) 100 Jb) 50 Jc) 200 Jd) 102 Je) None of the above5.1.6bIf the company had been run byphysics knurds, what should theyhave called the Power Bar?A) The Force BarB) The Pressure BarC) The Energy BarD) The Chemical BarE) The Power Bar is fine3BANG! The sound wave from a fireworkcarries 1 J of energy (total!). Ifthe sound burst lasts .2 seconds, what isthe power of this sound wave?a) 1 Wb) .2 Wc) 5 Wd) 2 We) ??5.2.2A lawnmower runs for 10 minutes.Over that time, a total of 1 J of sound energy isreleased. How does the power of thelawnmower sound compare to that of thefirework sound?A) Greater than B) Less thanC) Equal to D) ??5.1.6b2On Monday I walk slowly up theGamow tower. This takes a certainamount of energy.On Tuesday, I run up as fast as I can.Compare the ENERGY and POWERon the two days:A) Energy expended is same, poweris more on TuesdayB) Power is same, more energyexpended on TuesdayC) Energy and power both the sameon both daysD) More energy and more powerexpended on TuesdayE) ??5.1.9You and I are standing next to each other,listening to the exact same sound.Our ears are identical.You listen for TWICE as long as I doHow does the power compare?How does the total energy received compare?How does the intensity received compare?A)You receive twice what I doB)You receive half what I doC)We receive the same5.1.10You and I are standing next to each other,listening to the exact same sound.Your ears are TWICE the area of mine!How does the power compare?How does the total energy received compare?How does the intensity received compare?A) You receive twice what I doB) You receive half what I doC) We receive the same45.1.11Flute #1 generates a sound withmaximum overpressure 2 N/m2Flute #2 makes a sound withmaximum overpressure 6 N/m2How does the intensity of the soundscompare?I(#2) / I(#1) = ….A) 3B) 6C) 9D) 12E) 36Practice with powers of 10What’s 1,000 * 10-12?A) 1E-11B) 1E-10C) 1E-9D) 1E-8E) Something else/???5.2.3There are two instruments, a trumpet anda flute. The trumpet produces a soundwith10x more intensity than that of theflute. The decibel level for the trumpetis…compared to the flute.a) 10 dB greaterb) 10 dB lessc) 1 dB greaterd) 1 dB lesse) Not enough information5.2.3bThere are two instruments, a trumpet and a flute. Thetrumpet produces a sound with100x more intensitythan that of the flute.The SIL (decibel level) for the trumpet is…compared tothe flute.a) 2 dB greaterb) 10 dB greaterc) 20 dB greaterd) 100 dB greatere) Other/Not enough information/???55.2.5If a sound is 0 dB, does that mean thatno energy is transferred?a) Yesb) Noc) ??5.2.6At a concert, the trumpet section isplaying 30 dB louder than theFrench horn section.The trumpet section is playing with… of the French horn section.a) 3x the intensityb) 10x the intensityc) 30x the intensityd) 1000x the intensitye) 1030x the intensity5.2.4What if the trumpet is 20x moreintense than the flute.Is the decibel level…a) Less than 10 dB higherb) 10 dB higherc) Between 10 and 20 dB higherd) 20 dB highere) More than 20 dB higher5.2.4biiA flute plays at 60 dB.A trumpet produces a sound 2x moreintense than the flute.The decibel level of the trumpet is…A) 120 dBB) 2 dBC) 80 dBD) 62 dBE) 63 dB65.2.4bA trumpet is 20x more intense than aflute.How many decibels louder is thetrumpet?A) 3 dB higherB) 12 dB higherC) 13 dB higherD) 20 dB higherE) 23 dB higher5.2.4cA trumpet is 22 dB more than the flute.The ratio of intensities, I(trumpet)/I(flute), is…A) 16B) 22C) about 30D) 160E) 10225.2.4dA violin is playing at 55 dB. If you add a second violin, what happens tothe SIL?A) Stays the same, still 55 dBB) Goes to 57 dBC) Goes to 58 dBD) Goes to 75 dBE) Goes to 110 dB5.2.4eA violin is playing at 60 dB. Whathappens to the SIL if there are 20violins playing?A) Goes to 73 dBB) Goes to 76 dBC) Goes to 80 dBD) Goes to 120 dBE) Goes to much more than 120 dB75.3.1There is a source in the centeremitting sound outward. How doesintensity of the sound at r compareto that at R?a) I(at r) > IRb) I(at r) < IRc) I(at r) = IRd) Not enough informationrR5.3.1How does the total power(Energy/second) passing throughthe whole spherical surface at rcompare to that at R?A) Pr>PRB) Pr<PRC) Pr=PRD) ??rR1 cm1 cmHow does the power passing through apatch of 1 cm2 at radius r compare tothat at R?5.3.1How does the total power(Energy/second) passing throughthe whole spherical surface at rcompare to that at R?A) Pr>PRB) Pr<PRC) Pr=PRD) ??How does the power passing through apatch of 1 cm2 at radius r compare tothat at R?5.3.1If R=2r, what is IR/Ir?a) 1b) 2c) 4d) .5e) .2585.3.3Standing 10 meters from the speakers atan outdoor concert, the SIL is 100 dB.Assuming “no losses”, how loud is it at20 meters? …. 80 meters?A) 50 dB ….. 33 dBB) 50 dB ….. 38 dBC) 94 dB ….. 88 dBD) 94 dB ….. 82 dBE) Something totally different5.4.1True or False: A background noisewith a sound level of 100 dB wouldbe distracting? (what couldproduce this sound?)a)Trueb)False5.4.2Rank the following sound levelsfrom
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