PhET-Simulations-for-Physics/C2/Energy-Skate-Park/English-timed
From Script | Spoken-Tutorial
Revision as of 15:42, 12 August 2022 by Nancyvarkey (Talk | contribs)
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. |