The length of two open organ pipes are l and $(l+\Delta l)$ respectively. Neglecting end correction, the frequency of beats between them will be approximate :

(1) $\frac{v}{2l}$

(2) $\frac{v}{4l}$

(3) $\frac{v\Delta l}{2l^2}$

(4) $\frac{v\Delta l}{l}$

(Here v is the speed of sound)

A tube closed at one end and containing air is excited. It produces the fundamental note of frequency of 512 Hz. If the same tube is open at both the ends the fundamental frequency that can be produced is :

(1) 1024 Hz

(2) 512 Hz

(3) 256 Hz

(4) 128 Hz

An empty vessel is getting filled with water, then the frequency of vibration of the air column in the vessel 

(1) Remains the same

(2) Decreases

(3) Increases

(4) First increases then decrease

If the velocity of sound in air is 350 m/s. Then the fundamental frequency of an open organ pipe of length 50 cm, will be

(1) 350 Hz

(2) 175 Hz

(3) 900 Hz

(4) 750 Hz

The fundamental note produced by a closed organ pipe is of frequency f. The fundamental note produced by an open organ pipe of same length will be of frequency

(1) $\frac{f}{2}$

(2) f

(3) 2f

(4) 4f

If the velocity of sound in air is 336 m/s. The maximum length of a closed pipe that would produce a just audible sound will be : 

(1) 3.2 cm

(2) 4.2 m

(3) 4.2 cm

(4) 3.2 m

A cylindrical tube, open at both ends, has a fundamental frequency f₀ in air. The tube is dipped vertically into water such that half of its length is inside water. The fundamental frequency of the air column now is

1. 3 f₀/4

2. f₀

3. f₀/2

4. 2 f₀

If the length of a closed organ pipe is 1.5 m and the velocity of sound is 330 m/s, then the frequency for the second note is

(1) 220 Hz

(2) 165 Hz

(3) 110 Hz

(4) 55 Hz

A pipe 30 cm long is open at both ends. Which harmonic mode of the pipe is resonantly excited by a 1.1 kHz source? (Take the speed of sound in air = 330 ms^–1) 

1. First

2. Second

3. Third

4. Fourth