Question

The air in a closed tube 34 cm long is vibrating with 2 nodes and 2 antinodes and the temperature is 51oC. What is the wavelength of waves produced in air outside the tube when the temperature of air is 16oC?

Solution

Correct option is

32.1 cm

 

Since it is a closed tube and vibrating with 2 nodes and 2 antinodes, the length of the tube = λ.

Hence                        λ = 34

If n is the frequency and v51 is the velocity, then

                        

When the outside temperature is 16oC, let v16 be the velocity of sound and the wavelength. 

SIMILAR QUESTIONS

Q1

 

The figure below shows the wave y = A sin (ωt – kx), at any instant travelling in the +ve x-direction. What is the slope of the curve at B?

                                                                               

Q2

What is the ratio of the speed of sound in neon and water vapours at the same temperature? It is nearest to:

Q3

In case of the mechanical longitudinal wave y = A sin (ωt – kx) in air (density ρ), what is the relation between displacement amplitude and pressure amplitude?

Q4

A man beats a drum at a certain distance from a mountain. He slowly increases the rate of being and finds that the echo is not heard distinctly when the drum beating is at the rate of 40 per minute. He moves by 80 m towards the mountain and finds that the echo is again not heard distinctly when the rate of beating of the drum is 1 per second. What is the original distance of the man from the mountain?

Q5

In an experiment, it was found that a tuning fork and a sono-meter emitting its fundamental note, gave 5 beats per second both when the length of the wire was 1 metre and 1.05 metre. The velocity of transverse waves in the sono-meter wire is:

Q6

A slab of mass m is released from a height h0 from the top of a spring S’ of force constant  K. The maximum compression x of the spring is given by the equation:

                                                                           

Q7

A bob of mass m is oscillating as a simple pendulum with maximum amplitude θm. What is the maximum tension in the string?

Q8

A certain amount of acoustic energy is emitted in a uniform hemispherical pattern from a point source. At a distance of 5 m form the source the intensity is 5 W/m2. At a distance of 15 m the intensity will be:

Q9

 A 10 W source of sound of frequency 1000 Hz sends out waves in air. The displacement amplitude at a distance of 10 m from source will be: (Given velocity of sound = 350 m/s and density of air = 1.29 kg/m3)

Q10

The fundamental frequency of a longitudinal vibrating of a rod clamped at its centre is 1500 Hz. If the mass of the rod is 96 g the increase in its total length produced by a stretching force of 10 kg weight will be: