In the figure at the right is shown three graphs of the shapes of the same taut
ID: 2031047 • Letter: I
Question
In the figure at the right is shown three graphs of the shapes of the same taut elastic string in three different circumstances, labeled A, B, and C. In some of the problems below, the string represents a guitar string, tied down at both ends, while in others, it is part of a very long telephone wire whose ends are not shown. Be careful to note which is which for each problem! The string is light enough that the effects of gravity can be ignored. In each case, the bit of string at the position x = 23 cm is painted blue. millimeters 10 20 30 centimeters 1. Suppose the three graphs all represent the same string, tied down at x = 0 and x = 70 cm, and at the same tension. What can you say about the three frequencies of oscillation? millimeters 10 20 30 40 centimeters 50 60 70 milimeters 10 20 30 40 centimeters 50 60 70 O Situation A has the highest frequency. O Situation B has the highest frequency. O Situation C has the highest frequency. O The three frequencies are all the same. O You cant say anything from the information given. 2. Suppose the three graphs all represent the same string, tied down at x = 0 and x = 70 cm, but their tensions have been adjusted so that all three situations are all oscillating at the same frequency. What can you say about the tensions in the three cases? O You cant adjust the tensions to make the frequencies the same since the wavelengths are different. O The tension in string C is the greatest. O The tension is string A is the greatest. O All three tensions are the same. O You cant say anything from the information given.Explanation / Answer
1) Frequency means number of osillations in 1 second. As we can see case C shows more number of oscillations for given time. so Answer should be option third ( situation c has the highest frequency)
2) as frequency in case A is least, it will have the greatest tension. option third seems correct.
3) as we can see blue bead is at the origin line at the instant shown, so acceleration is zero at that point. option third is fine
4) for the long wire, at the instant shown, the velocity is downward towards the trough part of the wave. option second is correct
5) acceleration is zero in this case.