Question

A vibrating tuning fork is held over a water column with one end closed and the other open. As the water level is allowed to fall, a loud sound is heard for water levels separated by 27 cm. If the speed of sound in air is 340 m/s, what is the frequency of the tuning fork is ____________.

Answer 1

630 Hz.

Step-by-step explanation:

As we are considering the one end open pipe. So for the sound wave there will be a pressure node at the open end of the tube as at that place the molecules can not move back and forth. However on the closed end there will be a flow node as the water molecules their are moving back and forth. So it will produces the resonance at the positions 1/4, 3/4.......

we can find the wavelength by multiplying the levels distance by 2.

λ = 2 × 0.27 m = 0.54

f = Vs/λ

= 340/0.54

= 630 Hz