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AGE 19 fi- 2 < 04BN = ket PAGE (4 Sz —.V‘N&M—nfl\k (chall !~|wh|—.|®l~.’l* y"a@B,N = Wf-j Problem 23 Nick and Kara were lounging on rafts in the shallow waters of the beach at.Lake Bluebird. They were spaced 1.8 meters Anna Litical and walves are holding an elastic cord between them. Using a 1.6 meter long rope, they create a wave apart. A motor boat zoomed past creating ripples which traveled towards Nick and Kara. Nick and Xara's rafts began to bob which travels uA 2.4 m/s apd has a frequency of 1.5 Hz. What would be the new wavelength and speed if they double the up and down as the ripples passed by them, making exactly 4 up and down cycles in 8.4 seconds. When,Nick’s raft was at 3 frequency of vib: the cord? m . V/fi g: U_ fi . |_| \/ fi high point, Kara's raft was at a low point and there were no cfésts between their boats, Determine the wavelength, WU N 4 m i - ol € - 2 S= \/ frequency and speed of the ripples >.mw::8 that the ripples traveled in a direction parallel to the imaginary line connecting - - *U _ =t Nu* s V/ _ f 2 L =N w roblem 24: = = ' the two rafts. . S > - o w\1\/ = O@gv k/n\.mms\. A standing wave pattern is established in a 246-2mn lond rope. A snapshot of th moment in tirhe is Shown in = he rope / i —— |Ap|!m|PDD IN@C«. -4 the diagram below. Vibrations travel within thg rope at speeds of 22.7 m/s. Determine the frequency of vibration of the = 214Cm rope. - 3 A wave with a frequency of 12 2ft to right across a rope as shown in S :W \/ = N.hgb) c tire diagram at the right Positions A and B in the diagram are separated by a horizontal & - M && my/S distance of 42.8 cm. Positions C and D in the diagram are separated by a vertical distance . : \/ - Q m N m of 12.4 cm. ummnm::_:nham amplitude, wavelength, period and m_vomn of this wave. D- h : = 124 Cm - Tk o i =214, < < # Nh b.2em 33 = 0.08\3s ¢- Vfl Problem 18: S= Nm 22 Kh i 246 cm > B it . D - A rope is held tightly and shook until the standing wave pattern shown in the diagram - NN - - h at the right is established within the rope. The gistance A in the diagram is 3.27 Y = meters, The speed at which waves move along the rope is 2.62 m/s. \ my =3 Nd« 2. onnn:.:.:n the frequency of the waves creating the standing wave pattern. A= N ,& B - ) _ c.u,<mA :-:o _ &) P B 4. mm. P 4 / ) b. Determine the number of vibrational cycjgg which would be measured In 20.0 « s & nding wave w es _m:m 5 key as n in the ram at the right. The distance , s - 9 NAWAWA 55. point A to point B is known to be 4.69 meters. When not being vibrated as a standing secands. w & Z.18 fl a e _NG = iHc cles wave, a single pulse introduced into the medium at point A will travel to the opposite end and @ ‘ ‘ = back in 2.70 seconds. Determine the vibrational frequency of e ern. ' .20 20s A Problem 19: e . O mush TJQ dichaxe of .ewfl Anna Litical ties a rope to a tree, stands 7.2 m away, and vibrates the rope up and down with 28 _ = 1. m\» complete cycles in 5.0 seconds. The resulting standing wave pattern is shown in the diagram at the 05m Problem 26: right. Use this informatign and the diagram to determine the amplitude, wavelength, frequency and |~ A 144 cm long rope unde! speed - in th I-length sections). Onnmns_:m \— ” Nm - \SA=1.2m w \ (in three equal-leng ) A= 00 @ il fi Sbilz (A .rMmQ.; < = 4 2 vaov_oz.. 20: Problem 27: In the Standing Wave Lab, lab partners Chloe and Paige adjust the In a physics Iab, a rope is observed to make 240 complete vibrational cycles in 15 seconds. The length of the rope is 2.8 frequency of a mechanical oscillator in order to vibrate a 1.38 m length 28 meters and the measurements are made for the 6th harmonic (with six equal length sections). Determine Sm speed of the of elastic cord at one of its harmonic frequencies. The mnmm with — I waves in the rope. the pattern shown below when the frequency is set th 79.4 Hz. Determine the speed of the waves in the elastic cord. & _ Nm> _ _ W%DJ —_— S= = (0,552 mY 74 — S=438m A=0 G52 Bhblem 28: 32 fr.mrf‘.m : 4 . ) . ] Problem 21: - NV/H b. 2m V/ = W | m Winston and Michal hold opposite ends of a stretched rope. Winston introduces a 68-cm tall upward-displaced pulse on his 10s end while Michal m_ac_flvgcuig:dflwcnmm a42-cm «m: upwarg-displaced pulse on his end, The two puises meet in the In a physics demonstration, Mr. H establishes a standing wave pattern in a snakey by vibrating it up and down with 32___ middle of the rope. Coe dVTJ.\:(_.._ ve. |nder X renc vibrations in 10 secon: Om_&_a is holding the site end of the y and is standing 6.2 m from Mr. H's end. There are a. What is the ah:_ssn a_un_maman_..n of the rope when they completely uverap+ Woen+972cm = :C\ m J mw_. four equal length l , each pied by an antin cmfiisn the frequency, wavelength and speed of b. What would be the resultant displacement of the rope if Michal's pulse was displaced downward? the wave. TH 2 \ - O b o _F 3 & An hlmwrc.%m,n _%%\N\K‘P 5 e Problem 29: LB(m~-42(m =2timyu Problem 22 (challenge): S= \/fi 3Im-3% V During a classroom demonstration, Mr. H uses a wave machine donated to the school by Bell Telephone Company. The wave Gillian drives down Lake Avenue and observes an odd vib nal pattern of her ntenna. She observes it ] machine consists of two 1-meter length sections of 50 steel rods. The steel rods are connected to each other so that when vibrating back and forth in the manner shown at the right. There is an antinode at its free end and 2 node at the A the first rod is disturbed from a rest position, the disturbance travels along the medium from rod to rod. One of the sections location where the antenna mounts to the car. Vibrations travel through the 86 cm tall antenna at 5.0 x 10° m/s. consists of longer steel rods; disturbances move at 20 cm/s in this section. The other section consists of shorter steel rods; Determine the frequency of vibrations of the antenna. disturbances move at 80 cmy/s in this section. Mr, H connects the two sections together so that pylses can cross the boundary from one section to the other. He introduces a pulse with a length of 10 ¢cm into the slower section. Determine the length of this pulse when it crosses the boundary into the faster section.