PhET/C3/Radioactive-Dating-Game/English - Revision history

Madhurig at 10:59, 15 January 2019

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Madhurig at 20:02, 13 January 2019

2019-01-13T20:02:54Z

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Vidhya at 12:54, 9 January 2019

2019-01-09T12:54:52Z

Vidhya at 06:09, 1 January 2019

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Vidhya at 07:44, 21 December 2018

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Vidhya at 07:15, 21 December 2018

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Vidhya: Created page with " {|border=1 | | '''Visual Cue''' | | '''Narration''' |- | | '''Slide Number 1''' '''Title Slide''' | | Welcome to this '''tutorial''' on''' Radioactive Dating Game, '''an '..."

2018-10-11T06:59:36Z

Created page with " {|border=1 | | '''Visual Cue''' | | '''Narration''' |- | | '''Slide Number 1''' '''Title Slide''' | | Welcome to this '''tutorial''' on''' Radioactive Dating Game, '''an '..."

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{|border=1
| | '''Visual Cue'''
| | '''Narration'''

|-
| | '''Slide Number 1'''

'''Title Slide'''
| | Welcome to this '''tutorial''' on''' Radioactive Dating Game, '''an '''interactive PhET simulation.'''
|-
| | '''Slide Number 2'''

'''Learning Objectives'''

We will demonstrate,

'''Radioactive Dating Game PhET simulation'''
| | In this '''tutorial''', we will demonstrate, '''Radioactive Dating Game''', an '''interactive PhET simulation'''.
|-
| | '''Slide Number 3'''

'''System Requirements'''

'''Ubuntu Linux OS''' version 16.04

'''Java''' version 1.8.0

'''Firefox Web Browser''' version 60.0.2
| | Here I am using,

'''Ubuntu Linux OS''' version 16.04

'''Java''' version 1.8.0

'''Firefox Web Browser''' version 60.0.2
|-
| | '''Slide Number 4'''

'''Pre-requisites'''
| | Learners should be familiar with high school physics and chemistry.
|-
| | '''Slide Number 5'''

'''Learning Goals'''

Using this '''simulation''', we will look at

'''Radioactive decay''' and '''half life'''

Decay rates

Measurement of radioactivity

'''Radioactive dating'''

| |

Using this '''simulation''', we will look at

'''Radioactive decay''' and '''half life'''

Decay rates

Measurement of radioactivity

'''Radioactive dating'''
|-
| |
| | Please refer to the '''additional material''' provided with this '''tutorial'''.

Let us begin.
|-
| | '''Slide Number 6'''

'''Link for PhET simulation'''

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

[http://phet.colorado.edu/ http://phet.colorado.edu]
|-
| | Point to the '''file''' in '''Downloads folder'''.
| | I have already downloaded the '''Radioactive Dating Game simulation''' to my '''Downloads folder'''.
|-
| | Open the '''terminal''' by pressing '''Ctrl+Alt+T simultaneously'''.
| | To open the '''jar file''', open the '''terminal'''.
|-
| | At the '''terminal prompt''', type '''cd Downloads''' and press '''Enter'''.
| | At the '''terminal prompt''', type '''cd Downloads''' and press '''Enter'''.
|-
| | Type '''java space hyphen jar space radioactive-dating-game_en.jar'''.
| | Type '''java space hyphen jar space radioactive-dating-game_en.jar'''.
|-
| | Point to the '''browser''' address.
| | '''File''' opens in the '''browser''' in '''html format'''.
|-
| | Cursor on the '''interface'''.
| | This is the '''interface''' for the '''Radioactive Dating Game simulation'''.
|-
| |
| | Now we will explore the '''interface'''.
|-
| | Point to four '''screens''' in the '''interface'''.
| | The '''interface''' has four '''screens''':

'''Half Life'''

'''Decay Rates'''

'''Measurement'''

'''Dating Game'''
|-
| | Show the '''Half Life''' screen.
| | We are already looking at the '''Half Life''' screen.
|-
| | Point to the graph at the top of the screen.

Point to units of time along the '''x-axis'''.
| | At the top of the screen is an '''Isotope versus Time''' graph.

Pay attention to the units of time.
|-
| | Show '''Choose Isotope''' panel to the right.

Point to the three options in '''Choose Isotope''' panel.
| | On the right side of the screen, you see a '''Choose Isotope''' panel.

It has three options showing unstable nucleus decaying to stable nucleus.
|-
| | Point to the '''Bucket o’ Atoms''' in the '''simulation''' panel.

Point to the '''C-14''' atoms in the bucket and to the default selection of '''C-14'''.

Point to the “'''Add 10'''” button attached to the bottom of the bucket.
| | In the middle is the '''simulation''' panel containing a '''Bucket o’ Atoms'''.

Note that it contains '''C-14''' atoms as the default selection is '''C-14'''.

Attached to the bottom of the bucket is a '''button''' called “'''Add 10'''”.
|-
| | '''Slide Number 7'''

'''Stable and Unstable Nuclei'''

Electrostatic repulsion between protons in nucleus

Strong nuclear force ~ binding energy

High binding energy; stable nucleus

Low binding energy; unstable nucleus ~ radioactive

| |

'''Stable and Unstable Nuclei'''

There is electrostatic repulsion between positively charged protons inside the nucleus.

The strong nuclear force overcomes this electrostatic repulsion between protons.

The energy associated with this force is the binding energy.

The lower the binding energy, the more unstable is the nucleus.

Such an unstable nucleus is said to be radioactive.
|-
| | Point to '''Play/Pause button''' and '''Step button''' next to it.
| | Below this '''simulation''' panel is a '''Play/Pause button''' and a '''Step button''' next to it.
|-
| | Point to blue '''Reset All Nuclei button''' in '''simulation''' panel.
| | In this '''simulation''' panel is a blue '''Reset All Nuclei button'''.

This '''button''' lets you return to the start but with the selected isotope.
|-
| | Point to the white '''Reset All button''' below the right panel.
| | Below the right panel is a white '''Reset All button'''.

This button resets the '''simulation''' in this '''screen''' to all the default settings.
|-
| | Point to the default '''Isotope''' selection of '''C-14 to N-14'''.
| | The default '''Isotope''' selection is '''C-14 to N-14'''.
|-
| | Point to the '''Isotope versus time''' graph.

Point to vertical red dashed line labeled '''Half Life''' near the 5000 year mark.
| | Observe the '''Isotope versus time''' graph.

There is a vertical red dashed line labeled '''Half Life''' near the 5000 year mark.

The '''half-life''' of '''C-14''' is 5730 years.
|-
| | Point to red '''C-14''' symbol above the blue '''N-14''' symbol along the '''y-axis'''.
| | Along the '''y-axis''', you can see the red '''C-14''' symbol above the blue '''N-14''' symbol.

'''C-14''' atoms will appear in the upper row and '''N-14''' atoms in the lower one.
|-
| | Point to the red circle to the left of the '''Isotope''' label.

Point to '''hash symbols''' on the left of the circle.
| | To the left of the '''Isotope''' label is a red circle.

Numbers of '''C-14''' and '''N-14''' atoms shown by '''hash symbols''' will appear to the left of the circle.
|-
| | '''Slide Number 8'''

'''Radioactive Decay'''

Alpha decay

Beta decay

Gamma decay

Half-life
| | '''Radioactive Decay '''is the spontaneous conversion of an unstable nucleus into a stable nucleus.

It involves the release of subatomic particles and their energy as radiation.

It is of the following types:

'''Alpha decay'''

'''Beta decay'''

'''Gamma decay'''

'''Half-life''' is the time taken for half of the nuclei in a radioactive material to decay.
|-
| |
| | Let us get back to the '''simulation'''.
|-
| | Click on '''Add 10''' and immediately click on the '''Pause button'''.
| | Click on '''Add 10''' and immediately click on the '''Pause button'''.
|-
| | Point to the 10 '''C-14''' atoms added to the '''simulation''' panel.

Almost immediately, red '''C-14''' has started to decay to give blue '''N-14'''.
| | Ten '''C-14''' atoms have been added to the '''simulation''' panel.

Almost immediately, red '''C-14''' has started to decay to give blue '''N-14'''.
|-
| | Keep clicking on '''Step button''' to the right of '''Pause'''.
| | Keep clicking on '''Step button''' to the right of '''Pause'''.
|-
| | Show the red '''C-14''' atoms flying across the graph in the upper row.

Show the blue '''N-14''' atoms in the lower row.
| | Observe the red '''C-14''' atoms moving across the graph in the upper row.

In the lower row, blue '''N-14''' atoms appear as the '''C-14''' atoms decay.
|-
| | Point to the circle changing to blue.
| | Note how the circle changes to blue as more '''N-14''' atoms form.
|-
| | Keep clicking on '''Step button''' to the right of '''Pause''' until the circle is half red and half blue.
| | Keep clicking on '''Step button''' to the right of '''Pause''' until the circle is half red and half blue.
|-
| | Point to 5 blue '''N-14''' atoms on the left of the dashed half-life line.
| | Observe that, in the graph, there are 5 blue '''N-14''' atoms on the left of the dashed half-life line.

Out of 10 '''C-14''' atoms, half of them took 5730 years to decay into 5 '''N-14''' atoms.
|-
| | Point to 5 '''C-14''' and '''N-14''' atoms in the '''simulation''' panel.
| | Observe that there are 5 '''C-14''' atoms and 5 '''N-14''' atoms in the '''simulation''' panel also.

This is the definition of '''half-life'''.
|-
| | Click on '''Step button''' until you have 7 '''N-14 '''and 3 '''C-14''' atoms.
| | Click on '''Step button''' until you have 7 '''N-14 '''and 3 '''C-14''' atoms.
|-
| | Point to the 2 '''N-14''' atoms between the red dashed line and the 10000 mark.
| | Another 5730 years are taken for the remaining 5 '''C-14''' atoms to decay to 2.5 '''N-14''' atoms.

We see 2 '''N-14''' atoms between the red dashed line and the 10000 mark.
|-
| | Point to '''Add 10''' '''button''' and to the bucket.
| | If you click again on '''Add 10''', another 10 '''C-14''' atoms will be added to the '''simulation''' panel.

In this way, you can keep clicking '''Add 10''' until the bucket is empty.
|-
| |
| | Predict the number of '''C-14''' atoms remaining after different periods.
|-
| | Perform the same '''simulation''' for the other nuclei.
| | Perform the same '''simulation''' for the other nuclei.
|-
| | Click on the '''Decay Rates tab''' to go to that '''screen'''.

Show the '''interface'''.
| | Click on the '''Decay Rates tab''' to go to that '''screen'''.

The '''interface''' has a similar arrangement as the '''Half Life screen'''.

Please explore this '''screen''' in the same way.
|-
| | Click on the '''Measurement tab'''.
| | Now, let us click on the '''Measurement tab''' to go to that '''screen'''.
|-
| | Point to '''Tree''', the default selection under '''Choose an Object''' on the right.
| | In the right panel, under '''Choose an Object''', we will stay with '''Tree''', the default selection.
|-
| | Point to '''Carbon-14''', and '''Objects''' under '''Probe Type''' in top left.
| | In the top left, under '''Probe Type''', we will retain the default selections, '''Carbon-14''', and '''Objects'''.
|-
| | Click on '''Plant Tree button''' in the bottom right corner.

Point to the tree growing right where the '''probe''' is placed.
| | Click on '''Plant Tree button''' in the bottom right corner.

Observe that a tree grows right where the '''probe''' is placed.
|-
| | Immediately click on the '''Pause button'''.
| | Immediately click on the '''Pause button'''.
|-
| | Point to 100% seen above '''Probe Type''' in the upper left corner.
| | Observe 100% appear above '''Probe Type''' in the upper left corner.
|-
| | Keep clicking on the '''Step button''' to the right of '''Pause''' to move the '''simulation''' along.
| | Keep clicking on the '''Step button''' to the right of '''Pause''' to move the '''simulation''' along.
|-
| | Point to red line moving at the top of the graph along 100%.
| | Note that a red line moves at the top of the graph along 100%.
|-
| | Show '''% of C-14''' above the graph.
| | Above the graph, '''% of C-14''' is the default selection.
|-
| | Point to the white box below the graph.
| | The white box below the graph shows the number of years since the tree was planted.
|-
| | Point to the red line at the top of the graph.
| | The red line shows % of '''C-14''' remaining in the tree after those years after it was planted.
|-
| | Click on the second '''C-14''' to '''C-12''' ratio '''radio button''' above the graph.
| | Click on the second '''C-14''' to '''C-12''' ratio '''radio button''' above the graph.
|-
| | Point to the red line at the top of the graph.
| | Now the red line shows the '''C-14''' to '''C-12''' ratio in the tree after those years of planting it
|-
| | Click again on the % of '''C-14 radio button''' above the graph.
| | Click again on the % of '''C-14 radio button''' above the graph.
|-
| | Point to % in the top left, the tree and the white box below the graph.
| | Keep track of the % in the top left, the tree and the number of years below the graph.
|-
| | Note down the number of years and % of '''C-14''' when the tree

Loses its green color

Loses all its leaves

Falls over
| | Note down the number of years and % of '''C-14''' when the tree

Loses its green color

Loses all its leaves

Falls over
|-
| | Click on the '''Play button''' and let the '''simulation''' run until you see 55% above '''Probe Type'''.
| | Click on the '''Play button''' and let the '''simulation''' run until you see 55% above '''Probe Type'''.
|-
| | Keep clicking on the '''Step button''' until you see 50% in the top left window.
| | Keep clicking on the '''Step button''' until you see 50% in the top left window.
|-
| | Point to the tree and the number of years in the white box.
| | Observe the tree and the number of years seen below the graph.
|-
| | Point to 50% on '''y-axis''', to red line and to '''x co-ordinate'''.
| | Note the number of years after which you see 50% of '''C-14''' in the tree.
|-
| | Click on the '''C-14''' to '''C-12''' ratio '''radio button''' above the graph.
| | Click on the '''C-14''' to '''C-12''' ratio '''radio button''' above the graph.

Observe that this ratio has also dropped to half of what it was when the tree was planted.
|-
| | '''Slide Number 9'''

'''Other Measurements'''

Select '''Rock''' and '''Uranium-238'''

'''Objects''' selection

'''Probe''' → volcano → '''Erupt Volcano'''

When do you see 50% '''U-238''' in cooled volcanic rock?

'''Half-life''' of '''U-238''' is 4.5 billion years

Air '''radio button''' ('''probe''' in air)
| |

Choose the options shown here to carry out other measurements.
|-
| | Click on the last '''Dating Game tab'''.

Show the '''interface'''.
| | Let us click on the last '''Dating Game tab''' to go to that '''screen'''.

We can measure the levels of '''C-14, U-238''' or other '''custom nuclei''' in this '''screen'''.

We see objects on and below the ground on which we can place the probe to measure these levels.
|-
| | '''Slide Number 10'''

'''Radioactive Dating'''

Two isotopes of C: 12C and 14C

Both isotopes → CO2, living organisms

14C → 14N, 14C:12C organisms ~ atmosphere
| |

'''Radioactive Dating'''

Carbon has two isotopes: '''C-12''' and '''C-14'''.

Both are converted to carbon dioxide and are taken in by living organisms.

'''C-14''' decays to '''N-14''' but the ratio of '''C-14''' to '''C-12''' remains same in organisms and the atmosphere.
|-
| | '''Slide Number 11'''

'''Radioactive Dating-Cont’d'''

Death of organism, ratio and 14C fall

Radioactive dating, 14C:12C of sample vs recently dead specimens

Ur-Pb dating for rocks, artefacts etc
| |

'''Radioactive Dating-Continued'''

When an organism dies, it no longer takes in any carbon.

So levels of '''C-14''' and ratio of '''C-14''' to '''C-12''' fall.

Radioactive dating compares C-14 C-12 ratio of sample to recently dead specimens.

It estimates how long the organism has been dead.

'''Uranium-lead dating''' is used for rocks, archaeological artefacts etc
|-
| | Point to the graph on the top.

Point to the two '''radio buttons, % of C-14''' and '''C-14 to C-12''' ratio, for the '''y-axis'''.

Point to the '''x-axis'''.

Point to the vertical red dashed line.
| | On the top, we see the graph.

As before, we have two '''radio buttons, % of C-14''' and '''C-14 to C-12''' ratio, for the '''y-axis'''.

'''x-axis''' gives time in years.

The vertical red dashed line is the '''half-life'''.
|-
| | Point to these default selections:

Under '''Probe Type''', '''Carbon-14'''

'''Objects'''

'''% of C-14'''
| | Let us keep the following default selections:

Under '''Probe Type''', '''Carbon-14'''

'''Objects'''

'''% of C-14'''
|-
| | Drag the '''probe''' and place it on the animal skull on the ground, to the left.
| | We will drag the '''probe''' and place it on the animal skull on the ground, to the left.
|-
| | Point to the '''pop-up box''' next to the skull.

Show the '''text''', “'''Estimate age of Animal Skull'''”.

Show the empty box and “'''yrs'''” next to it.
| | Observe a '''pop-up box''' that appears next to the skull.

We see the '''text''', “'''Estimate age of Animal Skull'''” and below that an empty box and “'''yrs'''” next to it.
|-
| | Point to the '''Check Estimate button'''.
| | Below this is a '''Check Estimate button'''.
|-
| | Show 98.2% in the top left side, above '''Probe Type'''.
| | Observe that in the top left side, above '''Probe Type''', we see 98.2%.
|-
| | Drag the double-headed green arrow to the left.

Show 98.2% in the white box above the arrow.
| | Let us drag the double-headed green arrow above the graph.

In the white box above the arrow, % of '''C-14''' should be approximately 98.2%.
|-
| | Show '''t = 123 yrs''' in the white box below % of '''C-14'''.
| | Observe that it '''equals 123 yrs''' appears in the white box below % of '''C-14'''.

So after 123 years, approximately 98.2% '''C-14''' is left in the animal skull.
|-
| | Type 123 in the empty box below '''Estimate age of Animal Skull'''.

Click '''Check Estimate button'''.
| | Type 123 in the empty box below '''Estimate age of Animal Skull'''.

Click '''Check Estimate button'''.
|-
| | Point to green text-box with 123 years in its place with a green '''smiley''' face next to it.
| | The '''Estimate pop-up box''' disappears.

A green text-box with 123 years appears in its place with a green '''smiley''' face next to it.
|-
| |
| | We have successfully dated the animal skull by measuring the % of '''C-14''' remaining in it.
|-
| | '''Slide Number 12'''

'''Assignment'''

Estimate ages of all objects in '''Dating Game screen'''

Correlate age (years) with percentage of '''unstable''' nucleus

Correlate age (years) with depth at which object found

'''C-14''': animal remains; '''U-238''': rocks, objects
| |

As an '''assignment''',

Estimate ages of all the objects in the '''Dating Game screen'''.

Correlate age in years with the percentage of '''unstable''' nucleus.

Correlate age in years with the depth at which the object is found.

Remember to use '''C-14''' for animal remains and '''U-238''' for rocks and other objects.
|-
| |
| | Let us summarize.
|-
| | '''Slide Number 13'''

'''Summary'''

We have demonstrated,

'''Radioactive Dating Game PhET simulation'''
| |

In this '''tutorial''', we have demonstrated how to use the '''Radioactive Dating Game PhET simulation'''.
|-
| | '''Slide Number 14'''

'''Summary'''

Radioactive decay and half life

Decay rates

Measurement of radioactivity

Radioactive dating
| |

Using this '''simulation''', we looked at:

'''Radioactive decay''' and '''half life'''

Decay rates

Measurement of radioactivity

'''Radioactive dating'''
|-
| | '''Slide Number 15'''

'''About the Spoken Tutorial Project'''

Watch the video available at http://spoken-tutorial.org/ What_is_a_Spoken_Tutorial

It summarizes the Spoken Tutorial project

If you do not have good bandwidth, you can download and watch it
| | The video at the following link summarizes the '''Spoken Tutorial project'''.

Please download and watch it
|-
| | '''Slide Number 16'''

'''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 17'''

'''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 in this forum.
|-
| | '''Slide Number 18'''

'''Acknowledgement'''
| | This project is partially funded by '''Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching'''.
|-
| | '''Slide Number 19'''

'''Acknowledgement'''
| | '''Spoken Tutorial Project''' is funded by '''NMEICT, MHRD''', Government of India.

More information on this mission is available at this link.
|-
| |
| | This is '''Vidhya Iyer''' from '''IIT Bombay''', signing off.

Thank you for joining.
|-
|}

@@ Line 86: / Line 86: @@
 ||To open the '''jar file''', open the '''terminal'''.
 |-
-||At the '''terminal prompt''', type '''cd Downloads''' and press '''Enter'''.
+||At the '''terminal prompt''', type '''cd Downloads''' >> press '''Enter'''.
 ||At the '''terminal prompt''', type '''cd Downloads''' and press '''Enter'''.
 |-
-||Type '''java space hyphen jar space radioactive-dating-game_en.jar'''.
+||Type '''java hyphen jar radioactive-dating-game_en.jar'''>>  press '''Enter'''.
-||Type '''java space hyphen jar space radioactive-dating-game underscore en dot jar'''.
+||Type '''java space hyphen jar space radioactive-dating-game underscore en dot jar''', press '''Enter'''.
 |-
 ||Point to the '''browser''' address.
@@ Line 98: / Line 98: @@
 ||This is the '''interface''' for the '''Radioactive Dating Game simulation'''.
 |-
-||
+||Cursor on the interface.
 ||Now we will explore the '''interface'''.
 |-
@@ Line 148: / Line 148: @@
 Strong nuclear force is associated with binding energy
-If binding energy is low, the nucleus is unstable and is radioactive
+If binding energy is low, the nucleus is unstable and is radioactive.
-−
 ||'''Stable and Unstable Nuclei'''
@@ Line 218: / Line 217: @@
 '''Beta decay'''
-'''Gamma decay'''
+'''Gamma decay'''.
 |-
@@ Line 231: / Line 230: @@
 ||Let us get back to the '''simulation'''.
 |-
-||Click on '''Add 10''' and immediately click on the '''Pause button'''.
+||Click on '''Add 10''' >> immediately click on the '''Pause button'''.
 ||Click on '''Add 10''' and immediately click on the '''Pause button'''.
 |-
@@ Line 340: / Line 339: @@
 Loses all its leaves
-Falls over
+Falls over.
 |-
 ||Click on the '''Play''' or '''Step buttons''' to get approximately  50% in the top left window.
@@ Line 366: / Line 365: @@
 ||Let us click on the last '''Dating Game tab''' to go to that '''screen'''.
-We can measure levels of '''C-14, U-238''' or other '''custom nuclei''' in this '''screen'''.
+We can measure levels of '''C-14''', '''U-238''' or other '''custom nuclei''' in this '''screen'''.
 We see objects on and below the ground on which we can place the probe to measure these levels.
@@ Line 462: / Line 461: @@
 A green text-box with 123 years appears in its place with a green '''smiley''' face next to it.
 |-
-||
+||Point to the 123 yrs.
 ||We have successfully dated the animal skull by measuring the % of '''C-14''' remaining in it.
 |-

@@ Line 1: / Line 1: @@
@@ Line 150: / Line 149: @@
 Strong nuclear force ~ binding energy
 Low binding energy; unstable nucleus ~ radioactive
@@ Line 207: / Line 204: @@
 '''Radioactive Decay'''
 Alpha decay
@@ Line 214: / Line 212: @@
 Gamma decay
 | | '''Radioactive Decay '''is the spontaneous conversion of an unstable nucleus into a stable nucleus.
@@ Line 226: / Line 223: @@
 '''Gamma decay'''
 '''Half-life''' is the time taken for half of the nuclei in a radioactive material to decay.
@@ Line 374: / Line 380: @@
 We see objects on and below the ground on which we can place the probe to measure these levels.
 |-
-| | '''Slide Number 9'''
+| | '''Slide Number 10'''
 '''Radioactive Dating'''
@@ Line 395: / Line 401: @@
 So levels of '''C-14''' and ratio of '''C-14''' to '''C-12''' fall.
 |-
-| | '''Slide Number 10'''
+| | '''Slide Number 11'''
 '''Radioactive Dating-Cont’d'''
@@ Line 479: / Line 485: @@
 | | We have successfully dated the animal skull by measuring the % of '''C-14''' remaining in it.
 |-
-| | '''Slide Number 11'''
+| | '''Slide Number 12'''
 '''Assignment'''
@@ Line 505: / Line 511: @@
 | | Let us summarize.
 |-
-| | '''Slide Number 12'''
+| | '''Slide Number 13'''
 '''Summary'''
@@ Line 517: / Line 523: @@
 In this '''tutorial''', we have demonstrated how to use the '''Radioactive Dating Game PhET simulation'''.
 |-
-| | '''Slide Number 13'''
+| | '''Slide Number 14'''
 '''Summary'''
@@ Line 540: / Line 546: @@
 '''Radioactive dating'''
 |-
-| | '''Slide Number 14'''
+| | '''Slide Number 15'''
 '''About the Spoken Tutorial Project'''
@@ Line 553: / Line 559: @@
 Please download and watch it
 |-
-| | '''Slide Number 15'''
+| | '''Slide Number 16'''
 '''Spoken Tutorial workshops'''
@@ Line 560: / Line 566: @@
 For more details, please write to us.
 |-
-| | '''Slide Number 16'''
+| | '''Slide Number 17'''
 '''Forum for specific questions:'''
@@ Line 576: / Line 582: @@
 | | Please post your timed queries in this forum.
 |-
-| | '''Slide Number 17'''
+| | '''Slide Number 18'''
 '''Acknowledgement'''
 | | This project is partially funded by '''Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching'''.
 |-
-| | '''Slide Number 18'''
+| | '''Slide Number 19'''
 '''Acknowledgement'''