Home
Class 11
PHYSICS
Two speakers are driven by the same osci...

Two speakers are driven by the same oscillator with frequency of 200 Hz. They are located 4 m part on a vertical pole. A man walks straight towards the lower speaker in a direction perpendicular to the pole, as shown in figure. (i) How many times will he hear a minimum in sound intensity, and (ii) how far is he from the pole and at these moments ? Take the speed of sound to be 330 m/s, and ignore any sound reflections coming off the ground.
.

Text Solution

Verified by Experts

The correct Answer is:
(i) 2
(ii) 9.28 m and 1.99 m

(i) `lamda=(v)/(f)=(330)/(200)=1.65m,(d)/(lamda)=(4)/(1.65)=2.4242`
At infinity, path difference =0
As the approaches, the path difference changes as
`0,(lamda)/(2),lamda,(3 lamda)/(2),2 lamda`
`:.` Hence only minima will appear to man
(ii) For `Delta=(lamda)/(2)=sqrt(d^(2)+x_(1)^(2))-x_(1)and (3lamda)/(2)=sqrt(d^(2)+x_(2)^(2))-x_(2)`
`rArr x_(1)=9.28m,x_(2)=1.99 m`
Promotional Banner

Topper's Solved these Questions

  • WAVES AND OSCILLATIONS

    ALLEN|Exercise Part-1(Exercise-05)[A]|28 Videos
  • WAVES AND OSCILLATIONS

    ALLEN|Exercise Part-1(Exercise-05)[B]|42 Videos
  • WAVES AND OSCILLATIONS

    ALLEN|Exercise Part-1(Exercise-04)[A]|29 Videos
  • SEMICONDUCTORS

    ALLEN|Exercise Part-3(Exercise-4)|51 Videos

Similar Questions

Explore conceptually related problems

An oscillator of frequency 680 Hz drives two speakers . The speakers are fixed on a vertical pole at a distance 3 m from each other as shown in Fig. 7.103. A person whose height is almost the same as that of the lower speaker walks towards the lower speaker in a direction perpendicular to the pole. Assuming that there is no reflection of sound from the ground and speed of sound is v = 340 m//s , answer the following questions. How far is the person from the pole when he hears a minimum in sound intensity a second time ?

An oscillator of frequency 680 Hz drives two speakers . The speakers are fixed on a vertical pole at a distance 3 m from each other as shown in Fig. 7.103. A person whose height is almost the same as that of the lower speaker walks towards the lower speaker in a direction perpendicular to the pole. Assuming that there is no reflection of sound from the ground and speed of sound is v = 340 m//s , answer the following questions. As the person walks toward the pole , the total number of times that the person hears a minimum in sound intensity will be

An oscillator of frequency 680 Hz drives two speakers . The speakers are fixed on a vertical pole at a distance 3 m from each other as shown in Fig. 7.103. A person whose height is almost the same as that of the lower speaker walks towards the lower speaker in a direction perpendicular to the pole. Assuming that there is no reflection of sound from the ground and speed of sound is v = 340 m//s , answer the following questions. As the person walks towards the pole , his distance from the pole when he first hears a minimum in sound intensity is nearly

An oscillator of frequency 680 Hz drives two speakers . The speakers are fixed on a vertical pole at a distance 3 m from each other as shown in Fig. 7.103. A person whose height is almost the same as that of the lower speaker walks towards the lower speaker in a direction perpendicular to the pole. Assuming that there is no reflection of sound from the ground and speed of sound is v = 340 m//s , answer the following questions. At some instant , when the person is at a distance 4 m from the pole , the wave function ( at the person's location) that describes the waves coming from the lower speaker y = A cos (kx - omega t) , where A is the amplitude , omega = 2 pi v with v = 680 Hz (given) and k = 2 pi//lambda Wave function ( at the person's location) that describes waves coming from the upper speaker can be expressed as :

Two stereo speakers are separated by a distance of 2.40 m. A person stands at a distance of 3.20 m directly in front of one of the speakers as shown in figure. Find the frequencies in the audible range (20-2000 Hz) for which the listener will hear a minimum sound intensity. Speed of sound in air = 320 ms^-1

A guy wire attached to a vertical pole of height 18m is 24m long and has a stake attached to the other end.How far from the base of the pole should the stake be driven so that the wire will be taut?

A guy wire attached to a vertical pole of height 18m is 24m long and has a stake attached to the other end.How far from the base of the pole should the stake be driven so that the wire will be taut?

A man weighing 80 kg is standing at the centre of a flat boat and he is 20 m from the shore. He walks 8 m on the boat towards the shore and then halts.The boat weight 200 kg. How far is he from the shore at the end of this time ?