Wave Mechanics Question 760
Question: A steel rod 100 cm long is clamped at its mid-point. The funda-mental frequency of longitudinal vibrations of the rod is given to be 2.53 kHz. What is the speed of sound in steel
[AFMC 2000]
Options:
A) 5.06 km/s
B) 6.06 km/s
C) 7.06 km/s
D) 8.06 km/s
Show Answer
Answer:
Correct Answer: A
Solution:
If a rod clamped at middle, then it vibrates with similar fashion as closed organ pipe vibrates as shown. Hence, fundamental frequency of vibrating rod is given by $ n _{1}=\frac{v}{2l} $
Therefore $ 2.53=\frac{v}{4\times 10^{-1}} $
Therefore v = 5.06 km/sec.
BETA
