[填空题]
The A string of a violin is 32 cm long betvs3 ox+. qyw 5lgsw-qw pb1s6.ween fixed points with a fundamenta d zhux,9ymc4+l frequency of 4 9zmdx4 h+ucy,40 Hz and a mass per unit length of $6.1 \times10^{-4 }$ kg/m
(a) What are the wave speed and tension in the string? $ \times10^{2 }$ m/s N
(b) What is the length of the tube of a simple wind instrument (say, an organ pipe) closed at one end whose fundamental is also 440 Hz if the speed of sound is in air? m
(c) What is the frequency of the first overtone of each instrument? Hz Hz
