View source for ExpEYES/C2/Electro-Magnetism/English-timed

{|border = 1
|'''Time'''
|'''Narration'''

|-
|00:01
| Hello everyone. Welcome to this tutorial on '''Electro-magnetic induction'''.

|-
|00:06
| In this tutorial, we will demonstrate:
'''Electro-magnetic induction'''
Mutual induction of coils
Voltage induced by a rotating magnet
'''Resonance''' of driven pendulum 
and show '''circuit diagram'''s for our experiments.

|-
|00:26
| Here, I am using:
'''ExpEYES''' version 3.1.0
'''Ubuntu Linux OS''' version 14.10

|-
|00:35
| To follow this tutorial, you should be familiar with '''ExpEYES Junior''' interface. If not, for relevant tutorials, please visit our website. 

|-
|00:47
| Let's begin with the demonstration of '''Electro-magnetic Induction'''.

|-
|00:52
|In this experiment, wires of 3000 turns coil are connected to '''ground (GND)''' and ''' A1'''.

|-
|01:00
|To show the magnetic effect, a magnet with 5mm diameter and 10mm length is used.This is the '''circuit diagram'''.

|-
|01:11
| Let's see the result on the '''Plot window'''.

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|01:15
|A horizontal trace appears on the Plot window. Roll a paper and insert it inside the coil.

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|01:23
|Drop the magnet inside the rolled paper and move it up and down.

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|01:29
|Repeat the process until the '''induced voltage''' is captured and displayed. 

|-
|01:35
| On the '''Plot window''', click on '''Experiments''' button.

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|01:39
| '''Select Experiment''' list appears. Click on '''EM Induction'''. 

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|01:46
| Two new windows- '''Electromagnetic Induction''' and '''Schematic''' appear.
'''Schematic''' window shows the '''circuit diagram'''.

|-
|01:56
| On the '''Electromagnetic Induction''' window, click on '''Start Scanning''' button. Horizontal trace changes to a wave.

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|02:05
|It happens when the '''periodic scanning''' of the voltage coincides with the movement of the magnet. 

|-
|02:12
|This indicates that voltage is induced in the coil by a moving magnet. 

|-
|02:18
| Next, I will demonstrate '''mutual induction''' of two coils.

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|02:23
| In this experiment, '''A2''' is connected to '''SINE'''. '''SINE''' is connected to '''ground'''(GND) through a coil.

|-
|02:31
|And '''A1''' is connected to '''ground (GND)''' through a coil. This is the circuit diagram.

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|02:37
|Let's see the result on the '''Plot window'''.

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|02:40
|Click on '''A1''' and drag to '''CH1'''. '''A1 '''is assigned to '''CH1'''. 

|-
|02:47
| Click on '''A2''' and drag to '''CH2'''. '''A2''' is assigned to '''CH2'''.

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|02:55
|Move the '''msec/div''' slider to view the  '''applied waveform''' and '''induced waveform'''.

|-
|03:02
| A changing magnetic field causes '''induced voltage'''. You may not see any '''induced voltage''' on the secondary coil. 

|-
|03:12
|Keep the coils close to each other along the axis. Insert some '''ferromagnetic''' material along the axis.

|-
|03:20
|We have inserted a screw driver to '''induce voltage''' on the '''secondary coil'''. 

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|03:26
| Click and drag '''CH1''' to '''FIT'''. Click and drag '''CH2''' to '''FIT'''.

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|03:34
|Voltage and frequency of '''A1''' and '''A2''' are seen on the right.
Difference in the voltages of '''A1''' and '''A2''' is due to the '''induced voltage''' on the secondary coil. 

|-
|03:47
| Next, we will demonstrate voltage induced by a rotating magnet using '''DC motor''' and coils.

|-
|03:56
| In this experiment,
'''A1''' is connected to '''ground(GND)''' through a coil.
'''SQR2''' is connected to '''ground(GND)''' through a '''DC motor'''.

|-
|04:06
|A permanent magnet of 10mm diameter and 10mm length is mounted on DC motor.
'''A2''' is connected to '''ground (GND)''' through a coil. 

|-
|04:18
|This is the circuit diagram.

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|04:20
|Let's see the result on the '''Plot window'''.

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|04:23
| Under '''Setting Square waves''', set the frequency value to '''100Hz'''. Click on '''SQR2''' check-box.

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|04:34
| Click on '''A1''' and drag to '''CH1'''. '''A1''' is assigned to '''CH1'''.

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|04:41
|Click on '''A2''' and drag to '''CH2'''. '''A2''' is assigned to '''CH2'''.

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|04:47
|Move the '''msec/div''' '''slider''' to obtain the wave form.Move the volt/div slider to adjust the wave form.

|-
|04:57
|Click on '''CH1''' and drag to '''FIT'''.
Click on '''CH2''' and drag to '''FIT'''. 

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|05:05
| On the right side, you can see voltage and frequency. Please note, voltage and frequency values of the two alternating waveforms are almost the same. 

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|05:16
|This is because, as the magnet rotates, magnetic field around the coil constantly changes between the poles. 

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|05:24
|Rotation of the magnet results in alternating '''induced emf''' in the coil.

|-
|05:31
| Next, let's experiment with driven pendulum.

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|05:34
| If a pendulum oscillates with an induced magnetic field, it is called a '''driven pendulum'''.

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|05:41
|In this experiment, '''SQR1''' is connected to '''Ground (GND)''' using a coil.

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|05:47
|Button magnets are suspended in front of the coil with a paper strip as a pendulum. This is the circuit diagram.

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| 05:58
|Let's see the result on the '''Plot window'''.

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|06:01
|click on '''SQR1''' check box.

|-
|06:05
|Click on '''Experiments''' button. '''Select Experiment''' list appears. Select ''' Driven Pendulum'''.

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|06:15
|Two windows appear-
'''Schematic''' of '''Driven Pendulum''' and '''EYES Junior: Driven Pendulum'''.

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|06:23
| On the '''EYES Junior: Driven Pendulum''' window, drag the slider. As we drag the slider, the pendulum oscillates.

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|06:33
|Between "2.6 Hz" to "2.9Hz" pendulum oscillates with a maximum '''amplitude'''.
This is because, its '''resonant frequency''' is same as its '''natural frequency'''.

|-
|06:47
| Let's summarize.

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|06:49
| In this tutorial, we have learnt to demonstrate:
'''Electromagnetic induction'''
'''Mutual induction''' of coils
Voltage induced by a rotating magnet
Resonance of driven pendulum and show circuit diagrams for our experiments.

|-
|07:09
| As an assignment, demonstrate:
How to make an '''electromagnet'''
induction of a single coil with a magnet
Show circuit diagrams for the experiments.

|-
|07:22
|This video summarizes the '''Spoken Tutorial''' project.If you do not have good bandwidth, you can download and watch it.

|-
|07:30
|We conduct workshops using Spoken Tutorials and give certificates. Please contact us.

|-
|07:37
|The Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

|-
|07:44
| This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi.Thank you for joining.

|}