PhET-Simulations-for-Chemistry/C3/Rutherford-Scattering/English

Visual Cue	Narration
Slide Number 1 Title slide	Welcome to this tutorial on Rutherford Scattering simulation.
Slide Number 2 Learning objectives	In this tutorial we will, Demonstrate Rutherford Scattering, PhET simulation.
Slide Number 3 System Requirements	Here I am using- Ubuntu Linux OS version 14.04 Java version 1.7.0 Firefox Web Browser version 53.02.2
Slide Number 4 Pre-requisites	To follow this tutorial, Learner should be familiar with topics in high school science.
Slide Number 5 Learning Goals	Using this simulation we will learn, About Plum pudding and Rutherford atomic models. To visualise the Rutherford gold foil experiment. About behaviour of alpha particles. To identify the factors that affect the deflection of alpha particles.
	Now let us start the demonstration.
Slide Number 6 Link for PhET simulation http://phet.colorado.edu	Use the given link to download the simulation. http://phet.colorado.edu
Point to Rutherford Scattering simulation.	I have already downloaded Rutherford Scattering simulation to my Downloads folder.
Right click on Rutherford Scattering html file. Select Open with Firefox Web Browser option. Point to browser address.	To open the simulation, right click on Rutherford Scattering html file. Select Open with Firefox Web Browser option. File opens in the browser.
Point to interface.	This is the interface of Rutherford Scattering simulation.
Point to Rutherford Atom and Plum Pudding Atom	The interface has 2 screens- Rutherford Atom Plum Pudding Atom
Point to Plum Pudding Atom screen.	Lets begin with Plum Pudding Atom screen. J. J. Thomson proposed Plum Pudding atomic model. This model was proposed before Rutherford's atomic model.
Click on Plum Pudding Atom screen.	Click on Plum Pudding Atom screen to open it.
Point to experimental setup.	Left side of the screen has experimental set up for Plum Pudding atomic model.
Point to Alpha particles source and thin sheet of metal.	It consists of thin sheet of a metal above the Alpha Particles source.
Point to atomic scale. Point to a single atom.	Center of the screen has view box. It shows a single atom with 3.0 x 10-10 m atomic scale.
Point to red portion of an atom. Point to blue spheres in the atom. Point to atom.	In the atom, Red portion represents the positive charge, which is uniformly distributed. Small blue spheres represent electrons, which are embedded in the atom. There is no separation between positive charge and electrons in the atom.
Point to Legend and Alpha particle box.	Screen on the right side shows 2 boxes, Legend and Alpha particle.
Point to each component in the Legend box.	Legend box helps to identify the key components of the atom.
Point to Energy slider. Point to Traces checkbox. Click on Traces checkbox.	Alpha Particle box consists of, An Energy slider to change the energy of incoming alpha particles. Traces checkbox to show an alpha particle's trajectory. Check the Traces checkbox.
Point to Play/pause, step and reset button.	Bottom of the screen we have, Play/Pause button Step button and Reset button.
Click on blue button of Alpha Particles source.	To turn on the Alpha Particles source, click on the blue button.
Point to alpha particles beam.	Notice that alpha particles beam strikes the thin metal foil.
Point to traces in view box.	Observe the path of alpha particles inside the atom.
Point to alpha Particles.	All the alpha particles pass through the atom undeflected.
Point to atom.	This is because electrons are distributed evenly throughout the atom. The magnitude of negative and positive charges inside the atom is equal. This gives the most stable electrostatic arrangement. Therefore it makes an atom electrically neutral.
Cursor on the interface.	Plum Pudding model was able to explain overall neutrality of the atom.
Slide Number 7 Limitations of plum pudding model	Plum Pudding model of an atom failed to explain, The stability of an atom position of the nucleus in an atom
Slide Number 8 Plum Pudding Model	Plum Pudding model could not account for the atomic structure. But it provided the base, for the development of other atomic structure models.
Point to Rutherford Atom screen.	Let's move on to Rutherford Atom screen.
Click on Rutherford Atom screen.	Click on Rutherford Atom screen to open it.
Cursor on Rutherford Atom screen.	Rutherford Atom screen helps to visualise the rutherford's gold foil experiment.
Point to tools same as Plum Pudding atom screen. Point to Atom box.	Rutherford Atom screen has same tools as that of Plum Pudding atom screen. Additionally there is an Atom box below Alpha Particle box.
Point to Protons and Neutrons slider. Point to Protons and Neutrons number.	Atom box consists of, Protons and Neutrons sliders to change the composition of the nucleus. Here number of protons and neutrons is equal to that of gold atom.
Point to box at the center of the screen. Point to atoms in view box.	At the center of the screen, you will see a box. It represents a zoom in view of different atoms in the gold foil.
Point to atomic view and nuclear view.	Left side of the screen has 2 model views. They are atomic view and nuclear view.
Point to atomic view.	By default atomic view is selected. Atomic view gives an idea about, the behaviour of alpha particles as they travel through the atom.
Click on blue button of Alpha Particles source. Point to alpha particles beam.	Click on blue button to turn on the Alpha particles source. Notice that alpha particles beam strikes the thin gold foil.
Click on Traces checkbox.	Check the Traces checkbox to see the trajectories of alpha particles.
Point to traces.	Observe the traces of alpha particles as they approach the nuclei of the atoms.
Click on Pause button>>click on Step button.	Now pause the simulation and click on Step button.
Point to undeflected alpha particles. Point to alpha particles deflected by small angles. Point to alpha particles deflected by 180°.	Here, Most alpha particles are undeflected. Some of the alpha particles are slightly deflected. A very few alpha particles bounce back, that is deflected by nearly 180°.
Point to nuclear view. Click on nuclear view. Point to nucleus in zoom in view.	Let's see the behaviour of alpha particles in nuclear view. Click on nuclear view. Notice that in zoom in view, atoms are replaced by a single nucleus.
Click on Play button.	Now play the simulation.
Point to deflections of alpha particles.	Observe the deflections of alpha particles as they approach the nucleus.
Point to deflection of alpha particles.	Here n/p ratio for the gold atom is 1.5. Therefore alpha particles show a large deflection.
Cursor on interface.	Let's study the factors that affect the scattering of alpha particles.
Drag the Energy slider slowly towards min. Point to angles of deflection.	Drag the Energy slider towards min. Observe that, angles of deflection increases with the decrease in energy.
Cusror on the interface.	Next we will see, how change in composition of nucleus, affects scattering of alpha particles.
Drag the Energy slider to default position.	Lets start with small nucleus with few number of protons and neutrons. Drag the Energy slider back to its default position.
Drag Protons and Neutrons sliders towards 20. Point to nucleus.	Then drag the Protons and Neutrons sliders towards 20. Size of the nucleus becomes small.
Point to angles of deflection of alpha particles.	Observe the angles of deflection of alpha particles. Angle of deflection decreases with the decrease in protons and neutrons number.
	Here atom is stable as n /p ratio is 1.
Point to alpha particles far from nucleus. Point to alpha particles closer to nucleus.	Observe that, alpha particles far from the nucleus have almost no detectable deflection. While the alpha particles that are close to the nucleus are deflected.
Slide Number 9 Assignment	As an assignment, Try various combinations of protons and neutrons and check the deflections. Give an explanation for the change in the behaviour of the alpha particles.
	Let us summarise.
Slide Number 10 Summary	In this tutorial we have demonstrated, How to use Rutherford Scattering, PhET simulation.
Slide Number 11 Summary	Using this simulation we have learnt, About Plum pudding and Rutherford atomic models. To visualise the Rutherford gold foil experiment. About behaviour of alpha particles. To identify the factors that, affect the deflection of alpha particles.
Slide Number 12 About Spoken Tutorial project	The video at the following link summarizes the Spoken Tutorial project. Please download and watch it.
Slide Number 13 Spoken Tutorial workshops	The Spoken Tutorial Project team: conducts workshops using spoken tutorials and gives certificates on passing online tests. For more details, please write to us.
Slide Number 14 Forum for specific questions: Do you have questions in THIS Spoken Tutorial? Please visit this site Choose the minute and second where you have the question. Explain your question briefly Someone from our team will answer them.	Please post your timed queries on this forum.
Slide Number 15 Acknowledgements	This project is partially funded by Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching.
Slide Number 16 Acknowledgement	Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India. More information on this mission is available at this link.
	This is Meenal Ghoderao from IIT Bombay. Thank you for joining.

Contributors and Content Editors

Madhurig