Question

(a) The differential equation describing the motion of a stretched string 4. can be writ- ten y T Define the symbols that appear in this equation. [3 marks] (b) A uniform stretched string has length 2 m, mass 40 g and a fundamental fre- quency of 75 Hz. [4 marks] (i) Calculate the tension in the string. (ii) Write explicit expressions for the two lowest frequency normal modes of the string and sketch their shapes. (iii) The string is pulled aside a small distance at its centre and released from rest. Sketch a graph showing the displacement of the centre of the string as a function of time. Discuss the forces centre point during one cycle of the motion. 16 marks] on the element of the string at this 17 marks] C

Answer 1

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