Difference between revisions of "PhET/C2/Energy-Skate-park/English-timed"

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|-  
 
|-  
 
||00:06
 
||00:06
−
|| In this tutorial We will,
+
|| In this tutorial, We will demonstrate '''Energy Skate Park''', '''PhET simulation'''.  
−
 
+
−
* Demonstrate '''Energy Skate Park''', '''PhET simulation'''.  
+
  
 
|-  
 
|-  
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|| Here I am using-  
 
|| Here I am using-  
  
−
Ubuntu Linux OS version 14.04  
+
'''Ubuntu Linux OS''' version 14.04  
  
 
|-  
 
|-  
 
||00:22
 
||00:22
−
||Java version 1.7.0  
+
||'''Java''' version 1.7.0  
  
 
|-  
 
|-  
 
||00:26
 
||00:26
−
||Firefox Web Browser version 53.02.2  
+
||'''Firefox Web Browser''' version 53.02.2  
  
 
|-  
 
|-  
 
||00:32
 
||00:32
−
|| To follow this tutorial, learner should be familiar with topics in high school Physics.  
+
|| To follow this tutorial, learner should be familiar with topics in high school physics.  
  
 
|-  
 
|-  
 
|| 00:40
 
|| 00:40
−
|| Using this '''simulation''' we will learn,
+
|| Using this '''simulation''', we will learn:
  
 
1. About law of conservation of energy.  
 
1. About law of conservation of energy.  
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|-  
 
|-  
 
||00:48
 
||00:48
−
||2. To show pie chart and bar graphs for energy changes.  
+
||2. To show '''pie chart''' and '''bar graph'''s for energy changes.  
  
 
|-  
 
|-  
 
||00:53
 
||00:53
−
||3. To use '''Energy vs Position''' graph to show the energy value at a particular position.  
+
||3. To use '''Energy vs Position''' graph, to show the energy value at a particular position.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 01:27
 
|| 01:27
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||Potential energy, is the energy possessed by an object by virtue of its position.  
+
||'''Potential energy''' is the energy possessed by an object by virtue of its position.  
  
 
|-  
 
|-  
 
||01:34
 
||01:34
−
||'''PE = mgh ''' where, m is mass of object , g is acceleration due to gravity and h is height  
+
||'''PE = mgh ''' where '''m''' is mass of the object , '''g''' is acceleration due to gravity and '''h''' is height.
  
 
|-  
 
|-  
 
||01:43
 
||01:43
−
||Kinetic energy, is the energy possessed by a body due to its motion.  
+
||'''Kinetic energy''' is the energy possessed by a body due to its motion.  
  
 
|-  
 
|-  
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||'''KE =1/2 mv<sup>2</sup> '''
 
||'''KE =1/2 mv<sup>2</sup> '''
  
−
where, m is mass of object and v is velocity  
+
where '''m''' is mass of object and '''v''' is velocity.
  
 
|-  
 
|-  
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|-  
 
|-  
 
||  02:04
 
||  02:04
−
|| I have already downloaded, '''Energy skate park simulation '''to my '''Downloads '''folder.  
+
|| I have already downloaded '''Energy skate park simulation '''to my '''Downloads '''folder.  
  
 
|-  
 
|-  
 
|| 02:11
 
|| 02:11
−
|| To run the '''simulation''', open the terminal.  
+
|| To '''run''' the '''simulation''', open the '''terminal'''.  
  
 
|-  
 
|-  
 
||02:15
 
||02:15
−
||At the prompt type '''cd Downloads''' and press '''Enter'''.  
+
||At the prompt, type: '''cd Downloads''' and press '''Enter'''.  
  
 
|-  
 
|-  
 
|| 02:23
 
|| 02:23
−
|| Then type, '''java space hyphen jar space energy hyphen skate hyphen park underscore en dot jar''' and press '''Enter'''.  
+
|| Then type: '''java space hyphen jar space energy hyphen skate hyphen park underscore en dot jar''' and press '''Enter'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 02:41
 
|| 02:41
−
|| This is the interface of '''Energy skate Park simulation'''.  
+
|| This is the '''interface''' of '''Energy skate Park simulation'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 02:54
 
|| 02:54
−
|| Screen has a menu bar with menu items- '''File'''  
+
|| '''Screen''' has a menu bar with menu items- '''File''',
  
 
|-  
 
|-  
 
||03:00
 
||03:00
−
||'''Tracks'''  
+
||'''Tracks''',
  
 
|-  
 
|-  
 
||03:02
 
||03:02
−
||'''Help'''  
+
||'''Help'''.
  
 
|-  
 
|-  
 
|| 03:04
 
|| 03:04
−
|| Screen has a '''PhET skater''' oscillating in a default loop.  
+
|| Screen has a '''PhET skater''' oscillating in a default '''loop'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 03:19
 
|| 03:19
−
|| On the right side, there is a panel with controls.  
+
|| On the right side, there is a '''panel''' with '''control'''s.  
  
 
|-  
 
|-  
 
||03:24
 
||03:24
−
||These controls are used to, change the attributes in the '''simulation'''.  
+
||These controls are used to change the attributes in the '''simulation'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||03:49
 
||03:49
−
||By default '''PhET Skater''' with 75 kg mass is selected.  
+
||By default, '''PhET Skater''' with 75 kg mass is selected.  
  
 
|-  
 
|-  
 
||03:55
 
||03:55
−
||Click on '''Ok''' button.  
+
||Click on '''OK''' button.  
  
 
|-  
 
|-  
 
|| 03:58
 
|| 03:58
−
|| At the bottom of the screen we have, '''Sim Speed''' slider to control the speed of the animation.
+
|| At the bottom of the screen, we have '''Sim Speed''' slider to control the speed of the '''animation''',
  
 
|-  
 
|-  
 
||04:06
 
||04:06
−
||'''Play/Pause''' and '''Step''' buttons.
+
||'''Play/Pause''' and '''Step''' buttons,
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 04:13
 
|| 04:13
−
|| By default '''Sim Speed''' slider is on '''fast'''.  
+
|| By default, '''Sim Speed''' slider is on '''fast'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||04:27
 
||04:27
−
||Observe the purple dots on the track.  
+
||Observe the purple dots on the '''track'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||04:44
 
||04:44
−
||'''Kinetic energy'''  
+
||'''Kinetic energy''',
  
 
|-  
 
|-  
 
||04:46
 
||04:46
−
||'''Potential energy'''  
+
||'''Potential energy''',
  
 
|-  
 
|-  
 
||04:48
 
||04:48
−
||'''Total energy'''  
+
||'''Total energy''',
  
 
|-  
 
|-  
 
||04:50
 
||04:50
−
||'''Height'''  
+
||'''Height''',
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 04:58
 
|| 04:58
−
|| Now click on '''Play''' button to play the '''simulation'''.  
+
|| Now, click on '''Play''' button to play the '''simulation'''.  
  
 
|-  
 
|-  
 
|| 05:02
 
|| 05:02
−
|| On the right side panel under '''Energy Graphs''' section, click '''Show Pie Chart''' check-box.  
+
|| On the right side panel, under '''Energy Graphs''' section, click '''Show Pie Chart''' check-box.  
 
   
 
   
 
|-  
 
|-  
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|-  
 
|-  
 
||05:14
 
||05:14
−
||'''Pie chart''' shows conversion of Kinetic energy to Potential energy and vice-versa.  
+
||'''Pie chart''' shows conversion of kinetic energy to potential energy and vice-versa.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||05:26
 
||05:26
−
||This box helps to identify the energy changes in the Pie Chart.  
+
||This box helps to identify the energy changes in the '''Pie Chart'''.  
 
|-  
 
|-  
 
|| 05:31
 
|| 05:31
−
|| In this case potential energy is gravitational potential energy.  
+
|| In this case, potential energy is gravitational potential energy.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||07:37
 
||07:37
−
|| Drag the track to the left side to view the graph and '''skater''' simultaneously.  
+
|| Drag the '''track''' to the left side to view the graph and '''skater''' simultaneously.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||07:52
 
||07:52
−
||It represents, energy of the '''skater''' at a particular position on the track.  
+
||It represents energy of the '''skater''' at a particular position on the track.  
 
|-  
 
|-  
 
||07:58
 
||07:58
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|-  
 
|-  
 
|| 08:33
 
|| 08:33
−
|| At the bottom of the graph we have- '''Sim Speed''' slider,  
+
|| At the bottom of the graph, we have- '''Sim Speed''' slider,  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||09:57
 
||09:57
−
||By default '''Mass''' is 75 kg.  
+
||By default, '''Mass''' is 75 kg.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||10:31
 
||10:31
−
||In the '''Location''' section, by default '''Earth''' is selected.  
+
||In the '''Location''' section, by default, '''Earth''' is selected.  
  
 
|-  
 
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|-  
 
|-  
 
||10:44
 
||10:44
−
||Observe that '''Skater''' flies off because '''moon''' has low '''Gravity''' value.  
+
||Observe that '''Skater''' flies off because moon has low '''Gravity''' value.  
 
|-  
 
|-  
 
|| 10:50
 
|| 10:50
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|-  
 
|-  
 
||11:04
 
||11:04
−
||Here '''Total energy''' decreases as gravity on '''Moon''' is less than that of '''Earth'''.  
+
||Here, '''Total energy''' decreases as gravity on Moon is less than that of Earth.  
  
 
|-  
 
|-  
 
||11:10
 
||11:10
−
|| Similarly explore '''Jupiter''' and '''Space''' locations and compare the energy changes.  
+
|| Similarly, explore '''Jupiter''' and '''Space''' locations and compare the energy changes.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 11:21
 
|| 11:21
−
|| Let us study the energy distribution for tracks with and without '''Friction'''.  
+
|| Let us study the energy distribution for tracks with and without friction.  
  
 
|-  
 
|-  
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|-  
 
|| 11:30
 
|| 11:30
−
|| Scroll down to panel and click on '''Track Friction''' button.  
+
|| Scroll down to '''panel''' and click on '''Track Friction''' button.  
  
 
|-  
 
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|-  
 
||11:53
 
||11:53
−
||Here part of energy is converted to '''Thermal''' energy due to Friction.  
+
||Here, part of energy is converted to '''Thermal''' energy due to friction.  
  
 
|-  
 
|-  
 
||11:59
 
||11:59
−
|| This is due to the resistance in motion caused by '''Friction'''.  
+
|| This is due to the resistance in motion caused by friction.  
  
 
|-  
 
|-  
 
||12:04
 
||12:04
−
||'''Friction''' opposes the motion of the '''skater'''.  
+
||Friction opposes the motion of the '''skater'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 12:15
 
|| 12:15
−
|| As an assignment, Select '''Double Well''' track from '''Tracks''' menu and observe the energy changes.  
+
|| As an assignment:
 +
 
 +
Select '''Double Well''' track from '''Tracks''' menu and observe the energy changes.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||12:30
 
||12:30
−
||Find the changes in the '''thermal''' energy .
+
||Find the changes in the thermal energy  
  
 
|-  
 
|-  
 
||12:34
 
||12:34
−
||And give an explanation. (Hint-Right click on the '''Track''' and select '''Roller Coaster Mode''')  
+
||and give an explanation. (Hint-Right click on the '''Track''' and select '''Roller Coaster Mode''').
  
 
|-  
 
|-  
 
|| 12:43
 
|| 12:43
−
|| Using '''Tracks''' box, Create tracks and observe the change in energies.  
+
|| Using '''Tracks''' box, create tracks and observe the change in energies.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||12:52
 
||12:52
−
|| In this tutorial we have demonstrated, How to use '''Energy Skate Park''', '''PhET simulation'''.  
+
|| In this tutorial, we have demonstrated, How to use '''Energy Skate Park''', '''PhET simulation'''.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
||13:08
 
||13:08
−
||2.To show pie chart and bar graphs for energy changes.  
+
||2. To show pie chart and bar graphs for energy changes.  
  
 
|-  
 
|-  
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|-  
 
|-  
 
|| 13:29
 
|| 13:29
−
|| The video at the following link summarizes the Spoken Tutorial project.  
+
|| The video at the following link summarizes the '''Spoken Tutorial''' project.  
  
 
Please download and watch it.  
 
Please download and watch it.  
Line 651: Line 651:
 
|-  
 
|-  
 
|| 13:38
 
|| 13:38
−
|| 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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|-  
 
|-  
 
||14:03
 
||14:03
−
|| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.  
+
|| Spoken Tutorial Project is funded by '''NMEICT, MHRD,''' Government of India.  
  
 
|-  
 
|-  
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|| This is Meenal Ghoderao from IIT-Bombay.  
 
|| This is Meenal Ghoderao from IIT-Bombay.  
  
−
Thank you for joining  
+
Thank you for joining.
 
|-
 
|-
 
|}
 
|}

Latest revision as of 16:19, 11 August 2018

Time Narration
00:01 Welcome to this tutorial on Energy Skate Park simulation.
00:06 In this tutorial, We will demonstrate Energy Skate Park, PhET simulation.
00:14 Here I am using-

Ubuntu Linux OS version 14.04

00:22 Java version 1.7.0
00:26 Firefox Web Browser version 53.02.2
00:32 To follow this tutorial, learner should be familiar with topics in high school physics.
00:40 Using this simulation, we will learn:

1. About law of conservation of energy.

00:48 2. To show pie chart and bar graphs for energy changes.
00:53 3. To use Energy vs Position graph, to show the energy value at a particular position.
01:00 4. To change location and observe the energy changes.
01:04 5. About change in energy due to change in mass and friction.
01:09 According to law of conservation of energy, energy can neither be created nor destroyed.
01:17 It can only be converted from one form to another.
01:22 The total energy before and after the transformation is conserved.
01:27 Potential energy is the energy possessed by an object by virtue of its position.
01:34 PE = mgh where m is mass of the object , g is acceleration due to gravity and h is height.
01:43 Kinetic energy is the energy possessed by a body due to its motion.
01:49 KE =1/2 mv2

where m is mass of object and v is velocity.

01:57 Let us start the demonstration.
02:00 Use the given link to download the simulation.
02:04 I have already downloaded Energy skate park simulation to my Downloads folder.
02:11 To run the simulation, open the terminal.
02:15 At the prompt, type: cd Downloads and press Enter.
02:23 Then type: java space hyphen jar space energy hyphen skate hyphen park underscore en dot jar and press Enter.
02:37 Energy Skate Park simulation opens.
02:41 This is the interface of Energy skate Park simulation.
02:46 Using this simulation, let's see how energy transformations happen in real world applications.
02:54 Screen has a menu bar with menu items- File,
03:00 Tracks,
03:02 Help.
03:04 Screen has a PhET skater oscillating in a default loop.
03:09 To change the track of the skater, click on Tracks menu.
03:14 Menu shows a list of tracks to choose.
03:19 On the right side, there is a panel with controls.
03:24 These controls are used to change the attributes in the simulation.
03:29 Click on Reset to reset the simulation. Click on Yes to confirm the reset.
03:37 Click on Choose Skater button on the panel.
03:41 Choose Skater panel opens.
03:44 This panel shows different skaters along with their mass.
03:49 By default, PhET Skater with 75 kg mass is selected.
03:55 Click on OK button.
03:58 At the bottom of the screen, we have Sim Speed slider to control the speed of the animation,
04:06 Play/Pause and Step buttons,
04:10 Zoom in and zoom out buttons.
04:13 By default, Sim Speed slider is on fast.
04:17 Drag the Sim speed slider between slow and fast.
04:22 To show the path, click on Show Path button in Path section.
04:27 Observe the purple dots on the track.
04:30 Click on Stop button and then pause the simulation.
04:36 Click on any purple dot on the track.
04:40 The following information will be displayed:
04:44 Kinetic energy,
04:46 Potential energy,
04:48 Total energy,
04:50 Height,
04:52 Speed of skater.
04:54 Click on Clear button to clear the path.
04:58 Now, click on Play button to play the simulation.
05:02 On the right side panel, under Energy Graphs section, click Show Pie Chart check-box.
05:09 Observe that with Thermal check-box also gets selected.
05:14 Pie chart shows conversion of kinetic energy to potential energy and vice-versa.
05:20 Energy indicator box is shown on the top right corner of the screen.
05:26 This box helps to identify the energy changes in the Pie Chart.
05:31 In this case, potential energy is gravitational potential energy.
05:36 It is due to change in height of the skater in the gravitational field.
05:41 As the skater moves downwards, his potential energy decreases and kinetic energy increases.
05:49 As skater moves upwards his potential energy increases and kinetic energy decreases.
05:56 Drag the sim speed slider towards Slow.
06:00 You can still see a small amount of potential energy at the bottom of the track.
06:06 This is because track is at a height above the ground level.
06:11 Drag the track to the ground level.
06:15 Observe that skater has zero potential energy at the bottom of the track and zero kinetic energy at the top.
06:23 Now I will drag the track above the ground level.
06:27 Click on Potential Energy Reference check-box.
06:31 P.E=0 at this dotted line will display at the bottom of the screen.
06:37 Drag Potential Energy Reference line upwards to touch the bottom of the track.
06:43 Observe that now skater has zero potential energy at the bottom of the track.
06:49 Next, click on Bar Graph button.
06:52 A bar graph with four energies is shown.
06:56 Note the energy changes as the skater moves back and forth on the track.
07:02 Here total energy of the skater remains constant.
07:06 Therefore it obeys the law of conservation of energy.
07:10 Let us change the shape and height of the track.
07:14 Click on any blue point and drag.
07:17 Note the increase in Total energy with an increase in height of the track.
07:22 Close the Bar Graph.
07:24 Click on Reset button to reset the simulation.
07:29 Next click on Energy vs. Position button.
07:33 Energy vs Position graph will display.
07:37 Drag the track to the left side to view the graph and skater simultaneously.
07:43 Notice the energy changes with respect to position of skater.
07:48 Here you can see a moving dotted line.
07:52 It represents energy of the skater at a particular position on the track.
07:58 Graph has four energy check-boxes at the bottom.
08:02 To view the graph of any specific energy, un-check remaining check boxes.
08:09 Click on Pause button to pause the simulation.
08:13 Click on Copy button.
08:16 Copy button helps to show the energy values at particular position on the graph.
08:22 Close the graphs.
08:25 Now click on Energy vs. Time button.
08:29 Energy vs. Time graph opens.
08:33 At the bottom of the graph, we have- Sim Speed slider,
08:38 Stop/Go, Playback,
08:42 Step, Rewind and Clear buttons.
08:49 Click on Play button to play the simulation.
08:56 Click on Stop button.
08:59 Lets drag the sim speed slider between slow and fast.
09:04 Then click on Playback button.
09:07 Notice a violet vertical line moving across the path.
09:12 Note the kinetic, Potential and Total energy values at a given time.
09:20 Note that Total energy remains constant.
09:24 But, kinetic energy changes to potential energy and vice-versa.
09:29 Here Thermal energy is zero as there is no friction.
09:33 Close the Energy vs. Time graph.
09:36 Click on Reset button to reset the simulation.
09:40 Let us see how mass of the skater will affect the total energy.
09:45 Scroll to the bottom of the panel.
09:48 Click on Edit skater button.
09:51 Scroll down to see Mass text-box and Mass Slider.
09:57 By default, Mass is 75 kg.
10:01 Click on Energy Vs. Time button to open the graph.
10:06 Drag the Mass slider gradually towards 200.
10:10 Observe the change in energy as we change the skater's mass in the graph.
10:16 Close the Energy Vs. Time graph.
10:19 Now we will take the skater to different planets.
10:24 Scroll up the panel.
10:27 Click on Reset button to reset the simulation.
10:31 In the Location section, by default, Earth is selected.
10:35 Click on Energy vs. Time button.
10:39 Under Location section, click on Moon radio-button.
10:44 Observe that Skater flies off because moon has low Gravity value.
10:50 Click on Return Skater button.
10:53 Here Gravity value is 1.62 N/kg which is less than that of Earth.
11:00 This results in decrease in the speed of skater.
11:04 Here, Total energy decreases as gravity on Moon is less than that of Earth.
11:10 Similarly, explore Jupiter and Space locations and compare the energy changes.
11:17 Close the Energy vs. Time graph.
11:21 Let us study the energy distribution for tracks with and without friction.
11:26 Click on Reset button to reset the simulation.
11:30 Scroll down to panel and click on Track Friction button.
11:35 Scroll down to see Coefficient of Friction slider.
11:40 Click on Energy vs.Time button.
11:44 Drag the Coefficient of Friction slider gradually from None to Lots.
11:50 Observe the energy changes.
11:53 Here, part of energy is converted to Thermal energy due to friction.
11:59 This is due to the resistance in motion caused by friction.
12:04 Friction opposes the motion of the skater.
12:08 It causes him to lose energy and slow down.
12:12 Close the Energy vs. Time graph.
12:15 As an assignment:

Select Double Well track from Tracks menu and observe the energy changes.

12:24 Compare the energy changes in Double well track with Double Well Roller Coaster Mode.
12:30 Find the changes in the thermal energy
12:34 and give an explanation. (Hint-Right click on the Track and select Roller Coaster Mode).
12:43 Using Tracks box, create tracks and observe the change in energies.
12:49 Let us summarise.
12:52 In this tutorial, we have demonstrated, How to use Energy Skate Park, PhET simulation.
13:01 Using this simulation we have learnt,

1. About law of conservation of energy.

13:08 2. To show pie chart and bar graphs for energy changes.
13:13 3. To use Energy vs Position graph to show the energy value at a particular position.
13:20 4. To change location and observe the energy changes.
13:24 5. About change in energy due to change in mass and friction.
13:29 The video at the following link summarizes the Spoken Tutorial project.

Please download and watch it.

13:38 The Spoken Tutorial Project team conducts workshops using spoken tutorials and

gives certificates on passing online tests.

13:47 For more details, please write to us.
13:51 Please post your timed queries on this forum.
13:55 This project is partially funded by Pandit Madan Mohan Malaviya National Mission on Teachers and Teaching.
14:03 Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
14:11 More information on this mission is available at this link.
14:16 This is Meenal Ghoderao from IIT-Bombay.

Thank you for joining.

Contributors and Content Editors

Madhurig, PoojaMoolya, Sandhya.np14

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