Question

If the amplitude of a sound wave is doubled and its frequency reduced to one-fourth, the intensity of sound at the same point will

Solution

Correct option is

Decrease by a factor of 4

 

Intensity of a wave travelling in a medium of density ρ is given by

                                

If A becomes 2A and V becomes V/4, I will become

                                

SIMILAR QUESTIONS

Q1

An object producing a sound of frequency 400 Hz approaches a stationary person with a speed of 200 ms–1. The speed of sound is 300 ms–1. As the object flies past him, the person will note a change in frequency of  

Q2

 

The frequency of the sound of a car horn as received by an observer towards whom the car is moving differs from the frequency of the horn by 2.5%. If the speed of sound in air is

320 ms–1, the speed of the car is

Q3

A cylindrical tube, open at both ends, has a fundamental frequency V in air. The tube is dipped vertically in water so that half of it is inside water. The fundamental frequency of the air column now is

Q4

The intensity of a sound wave falls by 10% in travelling a distance of 1 metre in a medium. If the initial intensity of the sound wave was 100 decibels, its value after it passes through 3 metres thickness of the medium will be

Q5

A tube closed at one end containing air, produces, when excited, the fundamental note of frequency 512 Hz. If the tube is open at both ends, the fundamental frequency that can be excited in (in Hz)

Q6

Two second waves of equal intensity I produce beats. The maximum intensity of sound produced in beats will be

Q7

Two waves of wavelength 2 m and 2.02 m moving with the same speed superpose to produce 2 beats per second. The speed of each wave is

Q8

The potential energy of a particle executing simple harmonic motion at a distance x from the equilibrium position is proportional to

Q9

 

Two travelling waves

                      

and                

are superposed on a string. The distance between adjacent nodes is

Q10

At a certain instant a stationary transverse wave is found to have maximum kinetic energy. The appearance of the string at that instant is a