PhET/C2/Bending-Light/English-timed - Revision history

Sandhya.np14 at 12:11, 10 August 2018

2018-08-10T12:11:48Z

Sandhya.np14 at 12:10, 10 August 2018

2018-08-10T12:10:34Z

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Sandhya.np14 at 11:35, 10 August 2018

2018-08-10T11:35:43Z

Madhurig at 11:41, 9 August 2018

2018-08-09T11:41:52Z

Madhurig at 13:14, 7 August 2018

2018-08-07T13:14:41Z

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PoojaMoolya: Created page with "{| border = 1 |'''Time''' |'''Narration''' |- |00:01 |Welcome to this tutorial on '''Bending Light''', an interactive PhET simulation. |- |00:07 | In this tutorial we wil..."

2018-08-01T05:46:54Z

Created page with "{| border = 1 |'''Time''' |'''Narration''' |- |00:01 |Welcome to this tutorial on '''Bending Light''', an interactive PhET simulation. |- |00:07 | In this tutorial we wil..."

New page

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

|-
|00:01
|Welcome to this tutorial on '''Bending Light''', an interactive PhET simulation.

|-
|00:07
| In this tutorial we will learn,

How to use''' Bending Light, '''interactive PhET simulation.

|-
|00:14
| To follow this tutorial,

Learners should be familiar with topics in high school science.

|-
| 00:21
| Here I am using -

Ubuntu Linux OS Version 14.04

Java version 1.7.0

Firefox Web Browser Version 53.02.2.

|-
| 00:37
| Using this simulation we will learn,

Reflection of light

Refraction of light

Dispersion of light.

How reflection and refraction varies with different material media.

|-
|00:52
| We will also learn to,

Use optical instruments like prism and lens

Measure intensity of light

|-
|01:02
| Measure velocity of light and View different wave patterns.

|-
| 01:08
|Let’s define reflection, refraction and dispersion.

|-
| 01:14
| '''Reflection''' is bouncing back of a light ray after hitting any surface.

For example- A mirror reflects the image of the observer.

|-
| 01:26
|'''Refraction''' is bending of a light ray, when it enters a medium.

|-
|01:32
| Light changes its speed and angle of propagation as it enters a different medium.

For Example: Bending image of a Pencil in a beaker of water.

|-
| 01:45
|'''Dispersion ''' is a process of splitting of white light into seven colours.

|-
|01:51
| For Example, Formation of a Rainbow on a cloudy day.

|-
| 01:57
|| So, let's begin.

|-
| 01:59
| Use the given link to download the simulation.
[http://phet.colorado.edu/ http://phet.colorado.edu]

|-
| 02:03
|I have already downloaded '''Bending light''' simulation to my '''Downloads''' folder.

|-
| 02:09
| To open the simulation, right click on '''bending-light_en.html''' file.

|-
|02:14
| Select '''Open With Firefox Web Browser''' option. File opens in the browser.

|-
|02:23
|This is the interface for '''Bending Light''' simulation.
|-
|02:28
|The interface has three screens,

''' Intro '''

''' Prisms''' and ''' More Tools '''

|-
|02:35
|Let us begin our simulation with '''Intro''' screen. Click on '''Intro''' screen to open it.

|-
| 02:42
| This screen has, '''Ray''' and '''Wave''' radio buttons on the top left corner. A movable '''laser''' pointer to turn on the '''laser''' light.

|-
|02:53
| We can see green coloured arrows, when mouse pointer is, placed on the '''laser'''. These arrows show the direction, in which the '''laser''' moves.

|-
|03:06
| Click and drag the '''laser''', to move it from zero to 90 degrees. Let us bring the '''laser''' to its default position.

|-
| 03:16
| Now let’s move onto the tools at the bottom left.

|-
| 03:21
|Here we see a tool box. It consists of a, '''Protractor''' to measure angles '''Intensity''' tool to measure intensity of light.

|-
|03:32
| Below the tool box we have a check box to show '''Normal'''. A '''Reset ''' button is provided at the right hand side corner, to reset the simulation.

|-
| 03:44
| Let us begin the simulation.

|-
|03:47
| We can focus light in the form of a '''Ray ''', or a '''Wave''' depending on what we choose.

|-
|03:54
| By default '''Ray''' is selected. To turn on the '''laser''', click the red button on the '''laser''' pointer.

|-
| 04:03
| Notice that '''laser''' light gets reflected and refracted.

|-
| 04:09
| Observe that, as we drag the '''laser''' pointer, angle of reflection and refraction changes.

|-
| 04:17
|Let’s use the '''protractor''' tool to measure angle of, incidence refraction and reflection.

|-
|04:25
| Place the '''protractor''' at the intersection point of-

incident ray, normal, refracted and reflected rays.

|-
|04:35
| Observe that angle of incidence is equal to angle of reflection. Drag the '''protractor''' back to its place.

|-
|04:44
| Next we will move on to, right hand side of the '''Intro''' screen.

|-
|04:50
| Here, we have controls to measure '''refractive index''' in both the media.

|-
| 04:56
|There is a slider to change the material medium. Or buttons to click. Initially, the slider is near '''Air'''.

|-
|05:07
| As we drag the slider, medium changes from '''Air''' to '''Water''' and then to '''Glass'''.

|-
|05:15
| When medium is changed the angle of refraction changes. '''Index of Refraction(n)''' also changes.

|-
|05:24
| We can see the changing value in the box. Drag the slider back to '''Air''' in the upper medium.

|-
|05:32
| By default slider is on '''Water''' in the lower medium. Drag the slider and place it between '''Water''' and '''Glass''' in the lower medium.

|-
|05:44
| Now lets measure, the '''intensity''' of light using '''Intensity''' tool.

|-
| 05:49
| Click and drag the '''Intensity''' tool to the medium.

|-
|05:53
| '''Intensity''' tool consists of a '''magnifier''' and a '''meter''' to measure '''intensity''' of light.

|-
| 06:00
| I will place the '''magnifier''' on the incident light. Meter shows 100% intensity.

|-
| 06:08
| Now drag and place the '''magnifier''' on refracted light. Meter shows value as 86.08%. Intensity decreases because it depends on the medium.

|-
|06:24
| As we drag the medium slider, value on the intensity meter changes. This is because angle of refraction changes.

|-
|06:34
| Similarly place the '''magnifier''' on reflected light. '''Meter''' shows value as 13.55%.

|-
|06:44
| You can drag the slider to see a different value of intensity.

|-
| 06:51
| Now, change '''Ray''' to '''Wave''' and observe the '''bending of light'''.

|-
| 06:56
|Now we will move on to Prisms screen.

|-
| 07:00
|Click on '''Prisms''' screen, at the bottom of the interface.

|-
| 07:06
|In this screen we have the following tools-

Slider to change the '''environment'''

'''Monochromatic ray'''

|-
|07:15
| '''Monochromatic beam''' '''White light''' Slider to change '''wavelength''' of light.

|-
| 07:22
| At the bottom of the screen we have-

''' Prisms''' and '''lenses'''

|-
| 07:29
|Slider to change the '''Objects'''.

Check boxes for '''Reflections''', '''Normal''' and '''Protractor'''.

'''Reset''' button is at the right hand-side bottom corner.

|-
|07:43
|'''laser''' has a screw provided at its end. Direction of '''laser''' can be changed using this screw.

|-
| 07:52
|Here arrows indicate direction of motion. '''laser''' can be moved up and down.

|-
| 08:00
|Now let’s begin the simulation.

|-
| 08:03
|Click on '''Monochromatic beam'''. Click on the '''laser''' light.

|-
| 08:09
|Click on '''Reflections''' check box to see multiple reflections.

|-
| 08:14
| Place a '''Prism''' in the path of light. You can see bending of light.

|-
|08:21
| Move the '''wavelength''' slider gradually from red to violet. Notice the bending of light as '''wavelength''' changes.

|-
| 08:32
|'''Prism''' is provided with a screw at its corner.

|-
| 08:38
|Drag the screw to change the direction of the '''prism'''. As we change the direction notice the bending of light.

|-
| 08:47
|As an assignment
Change prism to glass slabs and observe the bending of light.

|-
| 08:54
|Now will see dispersion of light using white light.

|-
|08:59
| Click on '''White light''' tool. Observe the dispersion of light.

|-
|09:05
| Drag the '''Objects''' medium slider and observe the dispersion of light.

|-
| 09:11
|Place a lens in the path of dispersed beam of light. The dispersed beam of light shows multiple reflections.

|-
|09:26
| As an assignment

Use various lenses and observe the dispersion.

|-
| 09:32
|Change various '''Environments''' and observe the dispersion.

|-
| 09:37
|Now we move on to More Tools screen.

|-
| 09:41
|Click on '''More Tools''' screen. '''More Tools''' screen has a combination of tools from '''Intro''' and '''Prisms''' screens.

|-
| 09:51
|Tool box at the bottom has two additional tools:

'''Speed''' and '''Time'''.At the bottom we also have '''Angles''' check box. Click on the '''Angles''' check box.

|-
| 10:04
|Now we will change the '''laser''' light to Wave.

Additionally radio buttons-

'''Normal''' and '''Slow Motion''' Also, '''Play/Pause''' and '''Forward''' buttons appear.

|-
| 10:18
|let’s begin the simulation

|-
|10:21
|Turn on the '''laser''' light.

|-
|10:23
|Click on red button to turn on the '''laser''' pointer. let’s use the '''Time''' tool.

|-
|10:31
|Drag and place the '''Time''' tool in the medium. '''Time''' tool has two '''magnifiers''' and a '''Meter'''.

|-
|10:39
| Place one of the '''magnifiers''' on incident wave and observe the wave pattern. Now place the other '''magnifier''' on the refracted wave.

|-
|10:51
|Observe the wave pattern. It shows a '''phase shift'''.

|-
|10:56
| Place the '''magnifier''' on the reflected wave. Observe that, the new wave pattern is with reduced '''amplitude'''.

|-
|11:06
|This is because, the reflected wave has much lower '''intensity'''.

|-
|11:12
| Drag and place the '''Speed''' tool on the refracted wave. The speed is 0.67 c. Here c is velocity of light equal to 3x10^8 m/s. Value of speed decreases,

|-
|11:33
|This is because velocity of light decreases in a material medium.

|-
|11:39
|As an assignment,

Change material medium and notice the change in speed and wave pattern.

|-
| 11:48
| In this tutorial we have learnt,

How to use '''Bending Light''', interactive PhET simulation.

|-
|11:57
| Using this simulation we have learnt,

Reflection of light

Refraction of light

Dispersion of light

How reflection and refraction varies with different material media.

|-
|12:12
|We have also learnt to,

Use optical instruments like prism and lens

|-
|12:19
|Measure intensity of light Measure velocity of light and View different wave patterns.

|-
|12:29
| The video at the following link summarizes the Spoken Tutorial project. Please download and watch it.

|-
| 12:36
|The '''Spoken Tutorial Project '''team,conducts workshops using spoken tutorials and gives certificates on passing online tests.

|-
|12:46
|For more details, please write to us. Please post your timed queries on this forum.

|-
| 12:54
|This project is partially funded by, Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching.

|-
| 13:03
| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India. More information on this mission is available at this link.

|-
| 13:17
| This is Madhuri Ganapathi from IIT-Bombay signing off. Thank you for joining

|}

@@ Line 458: / Line 458: @@
 |-
 |12:19
-. Measure intensity of light, measure velocity of light and view different wave patterns.
+|2. Measure intensity of light, measure velocity of light and view different wave patterns.
 |-

@@ Line 9: / Line 9: @@
 |-
 |00:07
-| In this tutorial we will learn,
+| In this tutorial, we will learn how to use''' Bending Light''', interactive '''PhET simulation'''.
-−
-How to use''' Bending Light''', interactive '''PhET simulation'''.
 |-
 |00:14
-| To follow this tutorial,
+| To follow this tutorial, learners should be familiar with topics in high school science.
-−
-Learners should be familiar with topics in high school science.
 |-
@@ Line 23: / Line 19: @@
 | Here I am using -
-Ubuntu Linux OS Version 14.04
+'''Ubuntu Linux OS''' version 14.04
-Java version 1.7.0
+'''Java''' version 1.7.0
-Firefox Web Browser Version 53.02.2.
+'''Firefox Web Browser''' version 53.02.2.
 |-
 |  00:37
-| Using this simulation we will learn,
+| Using this simulation, we will learn:
 . Reflection of light
@@ Line 37: / Line 33: @@
 . Refraction of light
-. Dispersion of light.
+. Dispersion of light
-. How reflection and refraction varies with different material media.
+. How reflection and refraction vary with different material media.
 |-
@@ Line 45: / Line 41: @@
 | We will also learn to,
 . Use optical instruments like prism and lens
 . Measure intensity of light
 |-
 |01:02
-|7. Measure velocity of light and  View different wave patterns.
+|3. Measure velocity of light and  view different wave patterns.
 |-
@@ Line 65: / Line 61: @@
 |-
 | 01:26
-|Refraction, is bending of a light ray, when it enters a medium.
+|Refraction, is bending of a light ray when it enters a medium.
 |-
@@ Line 96: / Line 92: @@
 |-
 | 02:09
-| To open the simulation, right click on '''bending-light_en.html''' file.
+| To open the simulation, right-click on '''bending-light_en.html''' file.
 |-
 |02:14
 | Select '''Open With Firefox Web Browser''' option.
 File opens in the browser.
 |-
 |02:23
-|This is the interface for '''Bending Light simulation'''.
+|This is the '''interface''' for '''Bending Light simulation'''.
 |-
 |02:28
-|The interface has three screens,
+|The interface has three screens-''' Intro, Prisms''' and  ''' More Tools'''.
-−
-''' Intro '''
-−
-''' Prisms''' and  ''' More Tools'''.
 |-
@@ Line 123: / Line 114: @@
 |-
 | 02:42
-| This screen has, '''Ray''' and '''Wave''' radio buttons on the top left corner.
+| This screen has '''Ray''' and '''Wave''' radio buttons on the top left corner,
-A movable '''laser'''  pointer to turn on the '''laser'''  light.
+a movable '''laser'''  pointer to turn on the '''laser'''  light.
 |-
 |02:53
-| We can see green coloured arrows, when mouse pointer is, placed on the '''laser'''.
+| We can see green colored arrows when '''mouse pointer''' is placed on the '''laser'''.
-These arrows show the direction, in which the '''laser'''  moves.
+These arrows show the direction in which the '''laser'''  moves.
 |-
 |03:06
-| Click and drag the '''laser''',  to move it from zero to 90 degrees.
+| Click and drag the '''laser'''  to move it from zero to 90 degrees.
 Let us bring the '''laser'''  to its default position.
@@ Line 147: / Line 138: @@
 |Here we see a tool box.
-It consists of a, protractor to measure angles, '''Intensity''' tool to measure intensity of light.
+It consists of a protractor to measure angles, '''Intensity''' tool to measure intensity of light.
 |-
 |03:32
-| Below the tool box we have a check box to show '''Normal'''.
+| Below the tool box, we have a check-box to show '''Normal'''.
 A '''Reset''' button is provided at the right hand side corner, to reset the simulation.
@@ Line 175: / Line 166: @@
 |-
 | 04:09
-| Observe that, as we drag the '''laser'''  pointer, angle of reflection and refraction changes.
+| Observe that as we drag the '''laser'''  pointer, angle of reflection and refraction changes.
 |-
 | 04:17
-|Let’s use the protractor tool to measure angle of, incidence refraction and  reflection.
+|Let’s use the '''protractor''' tool to measure angle of incidence refraction and  reflection.
 |-
 |04:25
-| Place the protractor at the intersection point of-
+| Place the protractor at the intersection point of incident ray, normal, refracted and reflected rays.
-−
 incident ray, normal, refracted and reflected rays.
 |-
@@ Line 195: / Line 184: @@
 |-
 |04:44
-| Next we will move on to, right hand side of the '''Intro''' screen.
+| Next we will move on to right hand side of the '''Intro''' screen.
 |-
 |04:50
-| Here, we have controls to measure refractive index in both the media.
+| Here, we have controls to measure '''refractive index''' in both the media.
 |-
 | 04:56
-|There is a slider to change the material medium.
+|There is a '''slider''' to change the material medium, or buttons to click. Initially, the slider is near '''Air'''.
-Or buttons to click. Initially, the slider is near '''Air'''.
 |-
@@ Line 212: / Line 200: @@
 |-
 |05:15
-| When medium is changed the angle of refraction changes. '''Index of Refraction(n)''' also changes.
+| When medium is changed, the angle of refraction changes. '''Index of Refraction(n)''' also changes.
 |-

@@ Line 11: / Line 11: @@
 | In this tutorial we will learn,
-How to use''' Bending Light, interactive '''PhET simulation'''.
+How to use''' Bending Light''', interactive '''PhET simulation'''.
 |-
@@ Line 147: / Line 147: @@
 |Here we see a tool box.
-It consists of a, Protractor to measure angles, '''Intensity''' tool to measure intensity of light.
+It consists of a, protractor to measure angles, '''Intensity''' tool to measure intensity of light.
 |-
@@ Line 312: / Line 312: @@
 |-
 | 08:03
-|Click on '''Monochromatic beam'''. Click on the '''laser'''  light.
+|Click on monochromatic beam. Click on the '''laser'''  light.
 |-
@@ Line 324: / Line 324: @@
 |-
 |08:21
-| Move the wavelength slider gradually from red to violet.  Notice the bending of light as wavelength changes.
+| Move the wavelength slider gradually from red to violet.
 |-
@@ Line 347: / Line 349: @@
 |-
 |08:59
-| Click on '''white light''' tool. Observe the dispersion of light.
+| Click on white light tool. Observe the dispersion of light.
 |-
@@ Line 375: / Line 377: @@
 |-
 | 09:41
-|Click on '''More Tools''' screen. '''More Tools''' screen has a combination of tools from '''Intro''' and '''Prisms''' screens.
+|Click on '''More Tools''' screen.
 |-
@@ Line 383: / Line 387: @@
 '''Speed''' and '''Time'''.
-At the bottom we also have '''Angles''' check box. Click on the '''Angles''' check box.
+At the bottom we also have '''Angles''' check box.
 |-