Difference between revisions of "ExpEYES/C3/Characteristics-of-Sound-Waves/English-timed"

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(Created page with "{| border=1 ||'''Time''' ||'''Narration''' |- |00:01 |Hello everyone.Welcome to this tutorial on '''Characteristics of Sound Waves'''. |- |00:08 | In this tutorial we will l...")
 
 
(10 intermediate revisions by 3 users not shown)
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|-
 
|-
 
|00:01
 
|00:01
−
|Hello everyone.Welcome to this tutorial on '''Characteristics of Sound Waves'''.
+
|Hello everyone. Welcome to this tutorial on '''Characteristics of Sound Waves'''.
  
 
|-
 
|-
 
|00:08
 
|00:08
−
| In this tutorial we will learn to demonstrate:
+
| In this tutorial, we will learn to demonstrate:
 +
How to generate a sound wave,
 +
frequency response of a sound source,
  
−
* How to generate a sound wave
+
how to calculate velocity of sound,
−
 
+
'''interference''' and '''beats''' of sound waves,
−
* Frequency response of a sound source
+
−
 
+
forced oscillations of a sound source.
−
* How to calculate velocity of sound  
+
−
 
+
−
* Interference and Beats of sound waves  
+
−
 
+
−
* Forced oscillations of a sound source.
+
  
 
|-
 
|-
 
|00:29
 
|00:29
−
|And Show
+
|And, show:
  
−
* Xmgrace plots
+
'''Xmgrace plot'''s,
  
−
* Fourier Transforms and  
+
'''Fourier Transforms''' and  
  
−
* Circuit diagrams for our experiments.
+
'''Circuit diagram'''s for our experiments.
  
 
|-
 
|-
 
|00:38
 
|00:38
−
| Here I am using,
+
| Here, I am using:
−
* '''ExpEYES''' version 3.1.0
+
'''ExpEYES''' version 3.1.0,
−
* '''Ubuntu Linux''' OS version 14.10
+
'''Ubuntu Linux OS''' version 14.10.
  
 
|-
 
|-
 
|00:49
 
|00:49
−
| To follow this tutorial, you should be familiar with:
+
| To follow this tutorial, you should be familiar with '''ExpEYES Junior''' interface. If not, for relevant tutorials, please visit our website.  
−
'''ExpEYES Junior''' interface.If not, for relevant tutorials, please visit our website.  
+
  
 
|-
 
|-
 
|01:01
 
|01:01
−
| Let's first begin with definition of Sound.
+
| Let's first begin with definition of sound.
  
 
'''Sound''' is a vibration that propagates as an audible mechanical wave of pressure & displacement.
 
'''Sound''' is a vibration that propagates as an audible mechanical wave of pressure & displacement.
Line 50: Line 46:
 
|-
 
|-
 
|01:13
 
|01:13
−
|It requires a medium to propagate.The medium can be air, water or any metal surface.
+
|It requires a medium to propagate. The medium can be air, water or any metal surface.
  
 
|-
 
|-
 
|01:22
 
|01:22
−
| In this tutorial we will carry out various experiments to show characteristics of sound waves.
+
| In this tutorial, we will carry out various experiments to show characteristics of sound waves.
  
 
|-
 
|-
Line 62: Line 58:
 
|-
 
|-
 
|01:35
 
|01:35
−
|In this experiment, ground('''GND''') is connected to '''Piezo buzzer(PIEZO)'''.
+
|In this experiment, ground(GND) is connected to '''Piezo buzzer (PIEZO)'''.
  
−
'''Piezo buzzer(PIEZO)''' is connected to '''SQR1'''.
+
'''Piezo buzzer (PIEZO)''' is connected to '''SQR1'''.
  
 
|-
 
|-
 
|01:44
 
|01:44
−
|'''Microphone(MIC)''' is connected to '''A1'''.Here '''Piezo buzzer(PIEZO)''' is a source of sound.
+
|'''Microphone (MIC)''' is connected to '''A1'''. Here, '''Piezo buzzer(PIEZO)''' is a source of sound.
−
This is the circuit diagram.
+
This is the '''circuit diagram'''.
  
 
|-
 
|-
Line 81: Line 77:
 
|-
 
|-
 
|02:07
 
|02:07
−
| Click on '''SQR1''' check box.Frequency of '''SQR1''' is set to ''3500Hz''. A digitized sound wave is generated.
+
| Click on '''SQR1''' check-box. Frequency of '''SQR1''' is set to ''3500Hz''. A digitized sound wave is generated.
  
 
|-
 
|-
Line 89: Line 85:
 
|-
 
|-
 
|02:27
 
|02:27
−
| Click on '''SQ1''' and drag to''' CH2'''.Input data of '''SQ1''' is assigned to '''CH2'''.A square wave is generated.
+
| Click on '''SQ1''' and drag to''' CH2'''. Input data of '''SQ1''' is assigned to '''CH2'''. A square wave is generated.
  
 
|-
 
|-
 
|02:40
 
|02:40
−
| Drag the '''mSec/div''' slider to set in '''compressions''' and '''rear-fractions'''.
+
| Drag the '''mSec/div''' slider to set in '''compressions''' and '''rarefactions'''.
  
 
|-
 
|-
 
|02:48
 
|02:48
−
| Click on '''CH2 '''and drag to '''FIT'''.Voltage and frequency of '''SQ1''' is displayed on the right-side.
+
| Click on '''CH2 '''and drag to '''FIT'''. Voltage and frequency of '''SQ1''' are displayed on the right-side.
  
 
|-
 
|-
 
|02:59
 
|02:59
−
| Move the '''frequency''' slider to set in '''sound waves'''
+
| Move the frequency slider to set in sound waves.
  
 
|-
 
|-
Line 113: Line 109:
 
|-
 
|-
 
|03:19
 
|03:19
−
|Now we will demonstrate frequency response of '''Piezo buzzer'''.  
+
|Now, we will demonstrate frequency response of '''Piezo buzzer'''.  
  
 
|-  
 
|-  
 
|03:24
 
|03:24
−
| On the '''Plot window''' click on '''EXPERIMENTS''' button.'''Select Experiment''' list opens.Click on ''' Frequency Response''' from the list.
+
| On the '''Plot window''' click on '''EXPERIMENTS''' button. '''Select Experiment''' list opens. Click on ''' Frequency Response''' from the list.
  
 
|-
 
|-
 
|03:39
 
|03:39
−
| Two new windows '''Audio Frequency response Curve''' and '''Schematic''' open.'''Schematic''' window shows, circuit diagram of the experiment.
+
| Two new windows '''Audio Frequency response Curve''' and '''Schematic''' open. '''Schematic''' window shows the circuit diagram of the experiment.
  
 
|-
 
|-
 
|03:52
 
|03:52
−
| On the '''Audio Frequency response Curve''' window click on ''' START''' button.
+
| On the '''Audio Frequency response Curve''' window, click on ''' START''' button.
  
 
|-
 
|-
 
|03:59
 
|03:59
−
| '''Frequency response''' of the '''Piezo buzzer''' is set in.'''Frequency response''' has maximum '''amplitude''' at ''3700Hz''.  
+
| '''Frequency response''' of the '''Piezo buzzer''' is set in. '''Frequency response''' has maximum '''amplitude''' at ''3700Hz''.  
  
 
|-
 
|-
 
|04:11
 
|04:11
−
| On the same window click on '''Grace''' button.'''Grace''' window opens showing '''Frequency response Curve'''
+
| On the same window, click on '''Grace''' button. '''Grace''' window opens showing '''Frequency response Curve'''.
  
 
|-
 
|-
 
|04:22
 
|04:22
−
|Now we will measure velocity of the source of sound.
+
|Now, we will measure velocity of the source of sound.
  
 
|-
 
|-
 
|04:27
 
|04:27
−
| On the '''Plot window''' click on '''EXPERIMENTS''' button.
+
| On the '''Plot window''', click on '''EXPERIMENTS''' button.
−
'''Select Experiment''' list opens.Click on '''Velocity of Sound''' from the list.
+
'''Select Experiment''' list opens. Click on '''Velocity of Sound''' from the list.
 
|-
 
|-
 
|04:41
 
|04:41
−
|Two new windows '''EYES Junior: Velocity of Sound''' and '''Schematic''' open.'''Schematic''' window shows the circuit diagram of the experiment.
+
|Two new windows '''EYES Junior: Velocity of Sound''' and '''Schematic''' open. '''Schematic''' window shows the '''circuit diagram''' of the experiment.
  
 
|-
 
|-
 
|04:55
 
|04:55
−
| On '''EYES Junior: Velocity of Sound''' window click on '''Measure Phase''' button.
+
| On '''EYES Junior: Velocity of Sound''' window, click on '''Measure Phase''' button.
  
 
|-
 
|-
Line 157: Line 153:
 
|-
 
|-
 
|05:11
 
|05:11
−
|Click '''Measure Phase''' button to obtain different Phase values.
+
|Click '''Measure Phase''' button to obtain different '''Phase''' values.
  
 
|-
 
|-
 
|05:16
 
|05:16
−
|From the various '''Phase''' values we will use ''178deg'' and ''106deg'' to calculate velocity of sound.
+
|From the various '''Phase''' values, we will use ''178 deg'' and ''106 deg'' to calculate the velocity of sound.
  
 
|-
 
|-
 
|05:28
 
|05:28
−
|We can obtain these values when '''Piezo ''' is kept close and ''2cm'' away from the '''MIC'''.  
+
|We can obtain these values when '''Piezo''' is kept close and ''2cm'' away from the '''MIC'''.  
  
 
|-
 
|-
Line 173: Line 169:
 
|-
 
|-
 
|05:45
 
|05:45
−
| To calculate the value of '''velocity of sound''',we have the formula as shown:
+
| To calculate the value of '''velocity of sound''', we have the formula as shown.
 
Velocity of sound obtained from the experiment is 350m/sec.
 
Velocity of sound obtained from the experiment is 350m/sec.
  
 
|-
 
|-
 
|05:59
 
|05:59
−
|As an assignment, calculate the value of '''wavelength''' of sound.Formula: '''λ= v/f'''.
+
|As an assignment, calculate the value of '''wavelength''' of sound. Formula: '''λ= v/f'''(Lambda = v upon f).
  
 
|-
 
|-
 
|06:09
 
|06:09
−
| Now we will demonstrate:
+
| Now, we will demonstrate:
−
* Interference
+
'''Interference''',
  
−
* Beats  
+
'''Beats''',
  
−
* Xmgrace plot and  
+
'''Xmgrace plot''' and  
  
−
* Fourier Transform of the two sources of sound.
+
'''Fourier Transform''' of the two sources of sound.
  
 
|-
 
|-
 
|06:20
 
|06:20
−
| To show '''Grace''' plots in the experiments:
+
| To show '''Grace''' plots in the experiments,
  
 
|-
 
|-
 
|06:23
 
|06:23
−
|Make sure that you have installed
+
|make sure that you have installed:
  
−
* python-imaging-tk
+
'''python-imaging-tk''',
  
−
* grace
+
'''grace''',
  
−
* scipy and
+
'''scipy''' and
  
−
* python-pygrace on your system.
+
'''python-pygrace''' on your system.
  
 
|-
 
|-
 
|06:34
 
|06:34
−
|In this experiment we use two Piezo buzzers as source of sound.  
+
|In this experiment, we use two Piezo buzzers as source of sound.  
  
 
|-
 
|-
 
|06:41
 
|06:41
−
| In this experiment '''Piezo 1''' is connected to '''SQR1''' and ground'''(GND)'''.'''Piezo 2''' is connected to '''SQR2''' and ground'''(GND)'''.This is the circuit diagram.
+
| In this experiment, '''Piezo 1''' is connected to '''SQR1''' and ground'''(GND)'''. '''Piezo 2''' is connected to '''SQR2''' and ground'''(GND)'''. This is the circuit diagram.
  
 
|-
 
|-
Line 225: Line 221:
 
|-
 
|-
 
|07:06
 
|07:06
−
|Click on '''SQR1''' and '''SQR2''' check boxes.Frequency of '''SQR1 '''and''' SQR2''' is set to “3500Hz”.  
+
|Click on '''SQR1''' and '''SQR2''' check-boxes. Frequency of '''SQR1 '''and''' SQR2''' is set to “3500Hz”.  
  
 
|-
 
|-
Line 237: Line 233:
 
|-
 
|-
 
|07:29
 
|07:29
−
|Click on '''EXPERIMENTS''' button and select '''Interference of Sound'''.'''EYES: Interference of Sound''' window opens.
+
|Click on '''EXPERIMENTS''' button and select '''Interference of Sound'''. '''EYES: Interference of Sound''' window opens.
  
 
|-
 
|-
 
|07:39
 
|07:39
−
|At the bottom of the window, change '''NS''' that is '''number of samples''' value to ''1000''.
+
|At the bottom of the window, change '''NS''', that is, '''number of samples''' value to ''1000''.
  
 
|-
 
|-
 
|07:48
 
|07:48
−
|Click on '''SQR1''' and '''SQR2''' check boxes.Click on '''START''' button.'''Interference''' pattern is seen.  
+
|Click on '''SQR1''' and '''SQR2''' check-boxes. Click on '''START''' button. '''Interference''' pattern is seen.  
  
 
|-
 
|-
 
|08:00
 
|08:00
−
|Now click on '''Xmgrace''' button.A new window opens with a '''Grace''' pattern.
+
|Now, click on '''Xmgrace''' button. A new window opens with a '''Grace''' pattern.
  
 
|-
 
|-
 
|08:08
 
|08:08
−
|Now we will show '''Beats''' pattern.
+
|Now, we will show '''Beats''' pattern.
  
 
|-
 
|-
Line 262: Line 258:
 
|-
 
|-
 
|08:20
 
|08:20
−
| At the bottom of the window, Click on '''SQR1 '''and '''SQR2''' check boxes.
+
| At the bottom of the window, click on '''SQR1 '''and '''SQR2''' check-boxes.
  
 
|-
 
|-
 
|08:28
 
|08:28
−
|Click on '''START''' button.'''Beats''' pattern appears.
+
|Click on '''START''' button. '''Beats''' pattern appears.
  
 
|-
 
|-
 
|08:33
 
|08:33
−
|Now click on '''Xmgrace''' button.A new window opens with a '''Grace''' pattern.
+
|Now, click on '''Xmgrace''' button. A new window opens with a '''Grace''' pattern.
  
 
|-
 
|-
 
|08:42
 
|08:42
−
| Click on '''FFT'''.A new window opens with '''Fourier Transform'''.
+
| Click on '''FFT'''. A new '''window''' opens with '''Fourier Transform'''.
  
 
|-
 
|-
 
|08:49
 
|08:49
−
|To know more about '''Fourier Transform ''' please visit this webpage.'''https://en.wikipedia.org/wiki/Fourier_transform'''.
+
|To know more about '''Fourier Transform ''', please visit this webpage.
 +
'''https://en.wikipedia.org/wiki/Fourier_transform'''.
  
 
|-
 
|-
 
|08:55
 
|08:55
−
|Let us perform an experiment to show a low frequency sound wave.This is the circuit diagram.
+
|Let us perform an experiment to show a low frequency sound wave. This is the '''circuit diagram'''.
  
 
|-
 
|-
 
|09:03
 
|09:03
−
| Click on '''EXPERIMENTS''' button and select '''Interference of Sound'''.'''EYES: Interference of Sound''' window opens.
+
| Click on '''EXPERIMENTS''' button and select '''Interference of Sound'''. '''EYES: Interference of Sound''' window opens.
  
 
|-
 
|-
Line 306: Line 303:
 
|-
 
|-
 
|09:36
 
|09:36
−
|In this tutorials we have learnt to demonstrate:
+
|In this tutorial, we have learnt to demonstrate:
−
 
+
how to generate a sound wave,
−
* How to generate a sound wave
+
  
−
* Frequency response of a sound source  
+
'''Frequency response''' of a sound source,
  
−
* How to calculate velocity of sound waves
+
how to calculate velocity of sound waves,
  
−
* Interference and Beat pattern of sound waves  
+
'''Interference''' and '''Beat''' pattern of sound waves,
  
−
* Forced oscillations of sound source.  
+
'''forced oscillations''' of sound source.  
  
 
|-
 
|-
 
|09:56
 
|09:56
−
|And have shown:
+
|And, have shown:
  
−
* Xmgrace plots
+
'''Xmgrace plot'''s,
  
−
* Fourier Transforms and  
+
'''Fourier Transforms''' and  
  
−
* Circuit diagrams for our experiments.
+
'''Circuit diagrams''' for our experiments.
  
 
|-
 
|-
 
| 10:04
 
| 10:04
−
|As an Assignment,
+
|As an Assignment-
  
−
1. Capture a sound burst  
+
Capture a '''sound burst'''
  
−
2. Hint: A bell or a clap can be used as source of sound.This is the circuit diagram.
+
Hint: A bell or a clap can be used as source of sound. This is the circuit diagram.
  
 
|-
 
|-
 
|10:15
 
|10:15
−
|This video summarizes the Spoken Tutorial project.If you do not have good bandwidth, you can download and watch it.
+
|This video summarizes the '''Spoken Tutorial''' project. If you do not have good bandwidth, you can download and watch it.
  
 
|-
 
|-
 
|10:24
 
|10:24
−
|We conduct workshops using Spoken Tutorials and give certificates.Please contact us.
+
|We conduct workshops using Spoken Tutorials and give certificates. Please contact us.
  
 
|-
 
|-
 
|10:32
 
|10:32
−
|The Spoken Tutorial Project is funded by '''NMEICT, MHRD''' '''Government of India'''.
+
|The Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
  
 
|-
 
|-
 
|10:40
 
|10:40
−
|This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi.This is Sakina Sidhwa. Thank you for joining.
+
|This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi. This is Sakina Sidhwa.
 +
Thank you for joining.
  
 
|}
 
|}

Latest revision as of 09:06, 22 September 2017

Time Narration
00:01 Hello everyone. Welcome to this tutorial on Characteristics of Sound Waves.
00:08 In this tutorial, we will learn to demonstrate:

How to generate a sound wave, frequency response of a sound source,

how to calculate velocity of sound, interference and beats of sound waves,

forced oscillations of a sound source.

00:29 And, show:

Xmgrace plots,

Fourier Transforms and

Circuit diagrams for our experiments.

00:38 Here, I am using:

ExpEYES version 3.1.0, Ubuntu Linux OS version 14.10.

00:49 To follow this tutorial, you should be familiar with ExpEYES Junior interface. If not, for relevant tutorials, please visit our website.
01:01 Let's first begin with definition of sound.

Sound is a vibration that propagates as an audible mechanical wave of pressure & displacement.

01:13 It requires a medium to propagate. The medium can be air, water or any metal surface.
01:22 In this tutorial, we will carry out various experiments to show characteristics of sound waves.
01:30 Let's perform an experiment to show frequency of sound waves.
01:35 In this experiment, ground(GND) is connected to Piezo buzzer (PIEZO).

Piezo buzzer (PIEZO) is connected to SQR1.

01:44 Microphone (MIC) is connected to A1. Here, Piezo buzzer(PIEZO) is a source of sound.

This is the circuit diagram.

01:55 Let's see the result on the Plot window.
01:59 On the Plot window, under Setting Square waves, set the frequency as 3500Hz.
02:07 Click on SQR1 check-box. Frequency of SQR1 is set to 3500Hz. A digitized sound wave is generated.
02:20 Move the frequency slider to change the waveform.
02:27 Click on SQ1 and drag to CH2. Input data of SQ1 is assigned to CH2. A square wave is generated.
02:40 Drag the mSec/div slider to set in compressions and rarefactions.
02:48 Click on CH2 and drag to FIT. Voltage and frequency of SQ1 are displayed on the right-side.
02:59 Move the frequency slider to set in sound waves.
03:04 Sound wave produced by the Piezo buzzer is shown in black colour.
03:10 Amplitude of the wave changes as Piezo buzzer is moved closer and away from the MIC respectively.
03:19 Now, we will demonstrate frequency response of Piezo buzzer.
03:24 On the Plot window click on EXPERIMENTS button. Select Experiment list opens. Click on Frequency Response from the list.
03:39 Two new windows Audio Frequency response Curve and Schematic open. Schematic window shows the circuit diagram of the experiment.
03:52 On the Audio Frequency response Curve window, click on START button.
03:59 Frequency response of the Piezo buzzer is set in. Frequency response has maximum amplitude at 3700Hz.
04:11 On the same window, click on Grace button. Grace window opens showing Frequency response Curve.
04:22 Now, we will measure velocity of the source of sound.
04:27 On the Plot window, click on EXPERIMENTS button.

Select Experiment list opens. Click on Velocity of Sound from the list.

04:41 Two new windows EYES Junior: Velocity of Sound and Schematic open. Schematic window shows the circuit diagram of the experiment.
04:55 On EYES Junior: Velocity of Sound window, click on Measure Phase button.
05:02 We can obtain different Phase values by changing the distance between MIC and Piezo buzzer.
05:11 Click Measure Phase button to obtain different Phase values.
05:16 From the various Phase values, we will use 178 deg and 106 deg to calculate the velocity of sound.
05:28 We can obtain these values when Piezo is kept close and 2cm away from the MIC.
05:37 To obtain accurate results, ensure that MIC and Piezo buzzer are placed on the same axis.
05:45 To calculate the value of velocity of sound, we have the formula as shown.

Velocity of sound obtained from the experiment is 350m/sec.

05:59 As an assignment, calculate the value of wavelength of sound. Formula: λ= v/f(Lambda = v upon f).
06:09 Now, we will demonstrate:

Interference,

Beats,

Xmgrace plot and

Fourier Transform of the two sources of sound.

06:20 To show Grace plots in the experiments,
06:23 make sure that you have installed:

python-imaging-tk,

grace,

scipy and

python-pygrace on your system.

06:34 In this experiment, we use two Piezo buzzers as source of sound.
06:41 In this experiment, Piezo 1 is connected to SQR1 and ground(GND). Piezo 2 is connected to SQR2 and ground(GND). This is the circuit diagram.
06:56 Let's see the result on the Plot window.
07:00 On the Plot window, set frequency as 3500Hz.
07:06 Click on SQR1 and SQR2 check-boxes. Frequency of SQR1 and SQR2 is set to “3500Hz”.
07:20 A digitized sound wave is generated.
07:24 Move the frequency slider to change the waveform.
07:29 Click on EXPERIMENTS button and select Interference of Sound. EYES: Interference of Sound window opens.
07:39 At the bottom of the window, change NS, that is, number of samples value to 1000.
07:48 Click on SQR1 and SQR2 check-boxes. Click on START button. Interference pattern is seen.
08:00 Now, click on Xmgrace button. A new window opens with a Grace pattern.
08:08 Now, we will show Beats pattern.
08:11 Click on EXPERIMENTS button and select Interference of Sound.

EYES: Interference of Sound window opens.

08:20 At the bottom of the window, click on SQR1 and SQR2 check-boxes.
08:28 Click on START button. Beats pattern appears.
08:33 Now, click on Xmgrace button. A new window opens with a Grace pattern.
08:42 Click on FFT. A new window opens with Fourier Transform.
08:49 To know more about Fourier Transform , please visit this webpage.

https://en.wikipedia.org/wiki/Fourier_transform.

08:55 Let us perform an experiment to show a low frequency sound wave. This is the circuit diagram.
09:03 Click on EXPERIMENTS button and select Interference of Sound. EYES: Interference of Sound window opens.
09:13 At the bottom of the window, set the value of SQR1 to 100 and check the box.
09:21 Click on START button, a low amplitude wave is displayed.
09:29 Click on FFT to obtain a Grace plot of Fourier Transform.
09:34 Let's summarize.
09:36 In this tutorial, we have learnt to demonstrate:

how to generate a sound wave,

Frequency response of a sound source,

how to calculate velocity of sound waves,

Interference and Beat pattern of sound waves,

forced oscillations of sound source.

09:56 And, have shown:

Xmgrace plots,

Fourier Transforms and

Circuit diagrams for our experiments.

10:04 As an Assignment-

Capture a sound burst

Hint: A bell or a clap can be used as source of sound. This is the circuit diagram.

10:15 This video summarizes the Spoken Tutorial project. If you do not have good bandwidth, you can download and watch it.
10:24 We conduct workshops using Spoken Tutorials and give certificates. Please contact us.
10:32 The Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
10:40 This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi. This is Sakina Sidhwa.

Thank you for joining.

Contributors and Content Editors

Madhurig, Pratik kamble, Sandhya.np14

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