A long string is moved up and down with simple harmonic motion with a frequency of 42 Hz. The string is 543 m long and has a total mass is 47.2 kg. The string is fixed at both ends. If the string is fixed at a length of 28 m we find a third harmonic standing wave.
a)What is the tension in the string?
b) How long would the string need to be to find the second harmonic standing wave?