MCQ
An open pipe is in resonance in its $2^{nd}$ harmonic with tuning fork of frequency ${f_1}$. Now it is closed at one end. If the frequency of the tuning fork is increased slowly from ${f_1}$ then again a resonance is obtained with a frequency ${f_2}$. If in this case the pipe vibrates ${n^{th}}$ harmonics then
- A$n = 3,$ ${f_2} = \frac{3}{4}{f_1}$
- B$n = 3,$ ${f_2} = \frac{5}{4}{f_1}$
- ✓$n = 5,$ ${f_2} = \frac{5}{4}{f_1}$
- D$n = 5,$ ${f_2} = \frac{3}{4}{f_1}$



