Difference between revisions of "PhET/C3/Rutherford-Scattering/English-timed"

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|| 02:19
 
|| 02:19
||It shows a single atom with 3 into 10 to the power of  -10 meter atomic scale.
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||It shows a single atom with '''3 into 10 to the power of  -10 meter atomic scale'''.
 
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|| 02:26
 
|| 02:26
|| In the atom, red portion represents the positive charge which is uniformly distributed.  
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|| In the atom, red portion represents the positive '''charge''' which is uniformly distributed.  
  
 
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|| Screen on the right side shows 2 boxes, '''Legend''' and '''Alpha particle'''.
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|| '''Screen''' on the right side shows 2 boxes, '''Legend''' and '''Alpha particle'''.
  
 
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||This gives the most stable electrostatic arrangement.
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||This gives the most stable '''electrostatic''' arrangement.
  
 
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|| '''Plum Pudding''' model of an atom failed to explain,
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|| '''Plum Pudding''' model of an atom failed to explain:
  
The stability of an atom  
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the stability of an atom,
  
 
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|| Position of the nucleus in an atom
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|| position of the nucleus in an atom.
  
 
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||But it provided the base, for the development of other atomic structure models.
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||But it provided the base for the development of other atomic structure models.
  
 
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||Additionally there is an '''Atom''' box below '''Alpha Particle''' box.
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||Additionally, there is an '''Atom''' box below '''Alpha Particle''' box.
  
 
|-
 
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||04:56
 
||04:56
|| '''Atom''' box consists of, '''Protons''' and '''Neutrons''' sliders to change the composition of the nucleus.  
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|| '''Atom''' box consists of '''Protons''' and '''Neutrons''' sliders to change the composition of the nucleus.  
  
 
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|| 05:04
 
|| 05:04
||Here number of '''protons''' and '''neutrons''' is equal to that of gold atom.
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||Here, number of '''protons''' and '''neutrons''' is equal to that of gold atom.
  
 
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||It represents a zoom in view of different atoms in the gold foil.
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||It represents a '''zoom in''' view of different atoms in the gold foil.
  
 
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|| By default '''atomic view''' is selected.
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|| By default, '''atomic view''' is selected.
  
 
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|| 05:31
 
|| 05:31
||'''Atomic view''' gives an idea about, the behaviour of '''alpha''' particles as they travel through the atom.
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||'''Atomic view''' gives an idea about the behavior of '''alpha''' particles as they travel through the atom.
  
 
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||06:00
 
||06:00
|| Now pause the '''simulation''' and click on '''Step''' button.
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|| Now, pause the '''simulation''' and click on '''Step''' button.
  
 
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||A very few '''alpha''' particles bounce back, that is deflected by nearly 180°.
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||A very few '''alpha''' particles bounce back, that is, deflected by nearly 180°.
  
 
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|| 07:03
||Observe that, angles of deflection increases with the decrease in energy.  
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||Observe that angles of deflection increases with the decrease in energy.  
  
 
|-
 
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|| 07:09
 
|| 07:09
|| Next we will see, how change in composition of nucleus, affects scattering of '''alpha''' particles.
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|| Next we will see, how change in composition of nucleus affects scattering of '''alpha''' particles.
  
 
|-
 
|-
 
|| 07:16
 
|| 07:16
|| Lets start with small nucleus with few number of '''protons''' and '''neutrons'''.  
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|| Let's start with small nucleus with few number of '''protons''' and '''neutrons'''.  
  
 
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|| 07:50
 
|| 07:50
|| Observe that, '''alpha''' particles far from the nucleus have almost no detectable deflection.
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|| Observe that '''alpha''' particles far from the nucleus have almost no detectable deflection.
  
 
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|| 08:19
 
|| 08:19
|| In this tutorial we have demonstrated, How to use '''Rutherford Scattering''',''' PhET simulation'''.
+
|| In this tutorial, we have demonstrated how to use '''Rutherford Scattering''',''' PhET simulation'''.
  
 
|-
 
|-
 
|| 08:28
 
|| 08:28
|| Using this '''simulation''' we have learnt, About '''Plum pudding''' and '''Rutherford''' atomic models.
+
|| Using this '''simulation''', we have learnt: about '''Plum pudding''' and '''Rutherford''' atomic models,
 
+
 
|-
 
|-
 
|| 08:37
 
|| 08:37
||To visualise the Rutherford gold foil experiment.
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||to visualize the Rutherford gold foil experiment,
  
 
|-
 
|-
 
|| 08:41
 
|| 08:41
||About behaviour of '''alpha''' particles.
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||about behavior of '''alpha''' particles,
  
 
|-
 
|-
 
|| 08:45
 
|| 08:45
||To identify the factors that, affect the deflection of '''alpha''' particles.
+
||to identify the factors that affect the deflection of '''alpha''' particles.
  
 
|-
 
|-
 
|| 08:51
 
|| 08:51
|| The video at the following link summarizes the Spoken Tutorial project. Please download and watch it.
+
|| The video at the following link summarizes the '''Spoken Tutorial''' project. Please download and watch it.
  
 
|-
 
|-
 
|| 09:00
 
|| 09:00
|| The '''Spoken Tutorial Project '''team: conducts workshops using spoken tutorials and
+
|| The '''Spoken Tutorial Project '''team conducts workshops using spoken tutorials and gives certificates on passing online tests.
 
+
gives certificates on passing online tests.
+
  
 
|-
 
|-
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|| 09:25
 
|| 09:25
|| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
+
|| Spoken Tutorial Project is funded by '''NMEICT, MHRD,''' Government of India.
  
 
More information on this mission is available at this link.
 
More information on this mission is available at this link.

Revision as of 23:37, 13 August 2018

Time Narration
00:01 Welcome to this tutorial on Rutherford Scattering simulation.
00:06 In this tutorial, we will demonstrate Rutherford Scattering, PhET simulation.
00:13 Here I am using-

Ubuntu Linux OS version 14.04,

00:20 Java version 1.7.0,
00:25 Firefox Web Browser version 53.02.2
00:31 To follow this tutorial, learner should be familiar with topics in high school science.
00:39 Using this simulation, we will learn: about Plum pudding and Rutherford atomic models,
00:48 to visualize the Rutherford gold foil experiment,
00:52 about behavior of alpha particles,
00:56 to identify the factors that affect the deflection of alpha particles.
01:02 Now let us start the demonstration.
01:06 Use the given link to download the simulation.
01:11 I have already downloaded Rutherford Scattering simulation to my Downloads folder.
01:18 To open the simulation, right click on Rutherford Scattering html file.
01:26 Select Open with Firefox Web Browser option.
01:30 File opens in the browser.
01:33 This is the interface of Rutherford Scattering simulation.
01:38 The interface has 2 screens- Rutherford Atom, Plum Pudding Atom.
01:45 Let's begin with Plum Pudding Atom screen.
01:49 J. J. Thomson proposed Plum Pudding atomic model.
01:53 This model was proposed before Rutherford's atomic model.
01:58 Click on Plum Pudding Atom screen to open it.
02:02 Left side of the screen has experimental set up for Plum Pudding atomic model.
02:09 It consists of thin sheet of a metal above the Alpha Particles source.
02:15 Center of the screen has view box.
02:19 It shows a single atom with 3 into 10 to the power of -10 meter atomic scale.
02:26 In the atom, red portion represents the positive charge which is uniformly distributed.
02:33 Small blue spheres represent electrons which are embedded in the atom.
02:39 There is no separation between positive charge and electrons in the atom.
02:44 Screen on the right side shows 2 boxes, Legend and Alpha particle.
02:53 Legend box helps to identify the key components of the atom.
02:58 Alpha Particle box consists of- an Energy slider to change the energy of incoming alpha particles,
03:06 Traces check-box to show an alpha particle's trajectory.
03:11 Check the Traces check-box.
03:14 Bottom of the screen we have, Play/Pause button,
03:19 Step button and Reset button.
03:23 To turn on the Alpha Particles source, click on the blue button.
03:28 Notice that alpha particles beam strikes the thin metal foil.
03:33 Observe the path of alpha particles inside the atom.
03:37 All the alpha particles pass through the atom un-deflected.
03:42 This is because electrons are distributed evenly throughout the atom.
03:47 The magnitude of negative and positive charges inside the atom is equal.
03:53 This gives the most stable electrostatic arrangement.
03:57 Therefore it makes an atom electrically neutral.
04:01 Plum Pudding model was able to explain overall neutrality of the atom.
04:07 Plum Pudding model of an atom failed to explain:

the stability of an atom,

04:15 position of the nucleus in an atom.
04:19 Plum Pudding model could not account for the atomic structure.
04:24 But it provided the base for the development of other atomic structure models.
04:31 Let's move on to Rutherford Atom screen.
04:35 Click on Rutherford Atom screen to open it.
04:39 Rutherford Atom screen helps to visualise the rutherford's gold foil experiment.
04:45 Rutherford Atom screen has same tools as that of Plum Pudding atom screen.
04:51 Additionally, there is an Atom box below Alpha Particle box.
04:56 Atom box consists of Protons and Neutrons sliders to change the composition of the nucleus.
05:04 Here, number of protons and neutrons is equal to that of gold atom.
05:09 At the centre of the screen, you will see a box.
05:13 It represents a zoom in view of different atoms in the gold foil.
05:19 Left side of the screen has 2 model views.
05:23 They are atomic view and nuclear view.
05:27 By default, atomic view is selected.
05:31 Atomic view gives an idea about the behavior of alpha particles as they travel through the atom.
05:38 Click on blue button to turn on the Alpha particles source.
05:43 Notice that alpha particles beam strikes the thin gold foil.
05:48 Check the Traces check-box to see the trajectories of alpha particles.
05:54 Observe the traces of alpha particles as they approach the nuclei of the atoms.
06:00 Now, pause the simulation and click on Step button.
06:06 Here, Most alpha particles are undeflected.
06:11 Some of the alpha particles are slightly deflected.
06:15 A very few alpha particles bounce back, that is, deflected by nearly 180°.
06:22 Let's see the behaviour of alpha particles in nuclear view.
06:27 Click on nuclear view.
06:29 Notice that in zoom in view, atoms are replaced by a single nucleus.
06:35 Now play the simulation.
06:38 Observe the deflections of alpha particles as they approach the nucleus.
06:44 Here n/p ratio for the gold atom is 1.5. Therefore alpha particles show a large deflection.
06:53 Let's study the factors that affect the scattering of alpha particles.
06:59 Drag the Energy slider towards minimum.
07:03 Observe that angles of deflection increases with the decrease in energy.
07:09 Next we will see, how change in composition of nucleus affects scattering of alpha particles.
07:16 Let's start with small nucleus with few number of protons and neutrons.
07:22 Drag the Energy slider back to its default position.
07:27 Then drag the Protons and Neutrons sliders towards 20.
07:32 Size of the nucleus becomes small.
07:35 Observe the angles of deflection of alpha particles.
07:39 Angle of deflection decreases with the decrease in protons and neutrons number.
07:45 Here atom is stable as n /p ratio is 1.
07:50 Observe that alpha particles far from the nucleus have almost no detectable deflection.
07:57 While the alpha particles that are close to the nucleus are deflected.
08:02 As an assignment,

Try various combinations of protons and neutrons and check the deflections.

08:10 Give an explanation for the change in the behaviour of the alpha particles.
08:16 Let us summarise.
08:19 In this tutorial, we have demonstrated how to use Rutherford Scattering, PhET simulation.
08:28 Using this simulation, we have learnt: about Plum pudding and Rutherford atomic models,
08:37 to visualize the Rutherford gold foil experiment,
08:41 about behavior of alpha particles,
08:45 to identify the factors that affect the deflection of alpha particles.
08:51 The video at the following link summarizes the Spoken Tutorial project. Please download and watch it.
09:00 The Spoken Tutorial Project team conducts workshops using spoken tutorials and gives certificates on passing online tests.
09:09 For more details, please write to us.
09:13 Please post your timed queries on this forum.
09:17 This project is partially funded by Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching.
09:25 Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

More information on this mission is available at this link.

09:38 This is Meenal Ghoderao from IIT Bombay.

Thank you for joining.

Contributors and Content Editors

Madhurig, PoojaMoolya, Sandhya.np14