Apps-On-Physics/C3/Magnetism-and-Electromagnetism/English

Visual cue	Narration
Slide Number 1 Title slide	Welcome to the Spoken Tutorial on Magnetism and Electromagnetism.
Slide Number 2 Learning objective	At the end of this tutorial you will be able to, Draw magnetic field lines for a bar magnet. Verify right hand thumb rule. Verify Fleming's left hand and right hand rules. Simulate the working of a generator.
Slide Number 3 System Requirements	Here I am using, Ubuntu Linux OS version 16.04 Firefox web browser version 62.0.3
Slide Number 4 Pre-requities	To follow this tutorial, learner should be familiar with Apps on Physics. For the pre-requisites tutorials please visit this site. https://spoken-tutorial.org/
Slide Number 5 Apps on Physics	In this tutorial we will use, Magnetic Field of a Bar Magnet Magnetic Field of a Straight Current-Carrying Wire Lorentz Force and Generator Apps.
Point to the file in the downloads folder	I have already downloaded Apps on physics to my Downloads folder.
Right click on magneticfieldbar_en.htm file. Select option open with Firefox web Browser option.	Right click on magneticfieldbar_en.htm file. Select Open With Firefox web Browser option. Magnetic field bar App opens.
Point to the bar magnet. Point to the needle.	The App opens showing a magnet and a magnetic needle.
Point to Clear field lines and Turn magnet.	On the green panel there are two buttons. Clear field lines and Turn magnet.
Move the cursor on Red color of Bar magnet and green color.	Poles of a bar magnet and compass needle are represented by the following colors. Red for north pole and green for south pole.
Click on Turn magnet buttons.	Click on Turn magnet button. Observe that both bar magent and magnetic needle change their direction.
Place the cursor on the magnetic needle. Move the magnetic needle with the pressed mouse.	Let us draw the magnetic field lines. Place the cursor on the magnetic needle. Click on the magnetic needle and move the needle up to draw the magnetic lines. Continue to draw the lines as shown here.
Click on the Clear field lines button.	Click on the Clear field lines button.
Click on Turn magnet button.	Click on Turn magnet button.
Use the pressed mouse to draw the lines.	Again draw the magnetic lines around the magnet.
Point to the changed direction on the lines.	When we turn the magnet, the lines of force change the direction.
Point to the direction of arrows	The direction of magnetic field outside the bar magnet is from north to south. It is shown by the arrows.
Point to the maximum lines of fields. Ask question on the interface. Inside it from south to north.	Magnetic field is strongest inside the bar magnet. Outside the bar magnet it is strongest near the poles. What is the direction of magnetic field inside the bar magnet?
Point to Magnetic Fieldof a Straight Current-Carrying Wire	Next we will move on to Magnetic Field Line in a Current Carrying Wire App.
Right click on magneticfieldwire_en.htm file. Select Open with Firefox web browser option.	Right click on magneticfieldwire_en.htm file. Select Open with Firefox web browser option.
Cursor on the Setup.	The App opens showing magnetic field lines around a current carrying wire.
Point to Reverse current buttons.	On the right side of the screen we have a Reverse current button.
Point to the red arrow	The red arrow indicate the direction of the current. Note that the direction of current is opposite to that of electrons.
Point to minus and plus signs	The signs at the ends of the wire symbolize the terminals of the connected battery.
Point to concentric circles.	The concentric circles are the magnetic field around the current carrying wire.
	Let us find the direction of magnetic field using right hand thumb rule.
Use your right hand thumb to point the position of direction of the current.	Put your right hand thumb in the direction of the current.
Curl the fingers inside to palm.	Now curl your fingers inside. Fingers gives you the direction of magnetic field.
Slide Number 6 Assignment	As an assignment, Reverse the current flow and determine the magnetic field.
Right click on lorentzforce_en.htm file. Select Open with Firefox web Browser option.	Let us move on to the next App, Lorentz Force. Follow the same steps as we used for previous App to open htm file.
Point to the Setup.	Interface shows a horseshoe magnet through which a conducting wire is passed.
Point to the Blue coloured arrows.	The blue arrows shows the direction of the magnetic field.
Point to each button. On/Off Reverse current Turn magnet	On the green panel we have the following buttons. On/Off Reverse current Turn magnet.
Point to the wire.	When the circuit is open, the wire is shown in black colour.
Click on the On/Off button.	Click on the On/Off button to complete the circuit.
Point to the red wire and show the switch is on.	Notice that the wire is in conduction mode. This is indicated by the red coloured wire.
Point to the each check-box Current direction Magnetic field Lorentz force.	At the bottom, there are three check-boxes. These are Current direction, Magnetic field, Lorentz force.
Point to the black arrow.	The black arrow pointing towards right is the Lorentz force.
Show with the cursor the perpendicular state of Lorentz force.	Lorentz force is always perpendicular to the magnetic field.
Click on Turn magnet button.	To change the direction of magnetic field, click on the Turn magnet button.
Cursor on the interface.	Let us verify the direction of Lorentz force using Fleming’s left-hand rule.
Press F5 key on the keyboard.	Press F5 key on the keyboard to refresh the App.
Uncheck Lorentz force check-box.	First uncheck the Lorentz force check-box.
Click on On/Off button.	Click on On/Off button.
Use left hand fingers to find the force.	Now keep your fingers of the left hand as suggested here.
Now try to keep your fingers of left hand as index finger in the direction of magnetic field and middle finger in the direction of current and thumb points in the direction of Force.	Index finger pointing in the direction of magnetic field. Middle finger pointing in the direction of current. Thumb shows the direction of Lorentz force.
	Here the direction of Force is towards the right-side. This rule is Fleming’s left-hand rule.
Check the Lorentz force check-box.	Let us verify our answer by checking the Lorentz force check-box. Observe that the direction is same as shown in the App.
Slide Number 7 Assignment Reverse the current flow. Determine the direction of lorentz force using Fleming’s left hand rule.	As an assignment Reverse the current flow. Determine the direction of lorentz force using Fleming’s left hand rule.
	Now let us open the Generator App.
Open the App ,following the same procedure.(show the procedure)	I will open the App as before.
Cursor in the interface.	The App shows a generator.
Point to the generator.	An electrical generator converts mechanical energy into electrical energy.
Point to the magnet and rectangular loop inside the magnet.	The App opens showing a horseshoe magnet. A rectangular current carrying coil is inserted between the poles of the magnet.
Drag the slider and show the changes. Point to the rotating coil. Point to the value of 6 rot/min.	On the green panel, we can change the rotations per minute using the slider. By default the rectangular coil rotates 6 rotations per minute. We can change the rotation of the coil to a maximum of 12 rotations per minute.
Drag to 12 rotations per minute. Cursor on the graph. Point to show the peaks.	Increase the rotation to 12 rotation per minute. In the graph we can see two complete cycles in one minute. Here the frequency of the maximum output voltage is doubled.
Point to the path of red coloured wire from rectangular coil to voltage source.	The rectangular coil is connected to the voltage source through the slip rings.
Point to rectangular coil and the blue magnetic field lines.	Observe that the rectangular coil is rotating about an axis. This coil is perpendicular to the magnetic field.
Point to the wooden circular ring.	Here rotation of the rectangular coil is a source of mechanical energy.
Point to the red arrow.	Due to the rotation of the coil, curent is induced into the wire. The red arrow represents the direction of the induced current.
Point to the commutators.	In the green panel we can choose an AC generator or DC generator.
Point to Without commutator radio button. Click on With commutator radio button.	By default Without commutator an AC generator is selected. Select With commutator radio button. Commutator is a device for reversing the direction of flow of current. This device ensures that the current flows only in direct current mode. Hence With Commutator means, the generator is a DC generator.
Point to the graph of voltage v/s time.	On the top of the circuit, voltage v/s time graph is plotted. This is the graph of a DC generator.
In the graph point to show the moving blue point.(show one more pointer on the voltage source during editing)	In the graph, moving blue point indicates the change in voltage.
Click the Change direction button and show the change in direction of rectangular coil.	Change direction button changes the direction of the rectangular coil. Click on the Change direction button. Observe the change in the direction of rectangular coil. Also notice the change in the graph.
Press F5 key on the keyboard.	Press F5 key on the keyboard to restart the App.
Cursor on the interface.	We can find the direction of induced currect using Fleming’s right-hand rule.
Show the picture of Fleming’s left-hand rule here.	This rule is same as Fleming’s left-hand rule.
Click on Pause button when the .	Click on Pause button.
Show the picture of Fleming’s right hand rule.(The fingers of right hand means the same as flemings left hand)	Now arrange fingers of your right hand as shown in the figure.
Point to the check-box Direction of movement, Magnetic field, Induced current.	There are three check-boxes at the bottom of the green panel. Direction of movement, Magnetic field, and Induced current.
Uncheck Magnetic field check-box.	Uncheck the Magnetic field check-box. Notice that the magnetic field lines disappear.
Uncheck Direction of movement check-box.	In the similar way we can uncheck the remaining check-boxes if not required.
Press F5 key on the keyboard.	Press F5 key on the keybord to restart the App.
Point to the graph.	AC generator is an alternating current generator. So, here the graph shows positive as well as negative voltages.
Slide Number 8 Assignment Change the rotation per minute to 10.	As an assignment, Change the rotations per minute to 0, 3.0, 6.0 and 9.0 Note the changes in the movement of the coil and graph. Explain the reason for the changes.
	Let us summarise
Slide Number 9 Summary	Using these Apps we have, Drawn magnetic field lines of a bar magnet. Verified right hand thumb rule. Verified Fleming's left hand and right hand rules. Simulated the working of a generator.
Slide Number 10 Acknowledgement	These Apps were created by Walter Fendt and his team.
Slide Number 11 About Spoken Tutorial project.	The video at the following link summarises the Spoken Tutorial project. Please download and watch it.
Slide Number 12 Spoken Tutorial workshops.	The Spoken Tutorial Project team, conducts workshops and gives certificates. For more details, please write to us.
Slide Number 13 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 14 Acknowledgement	The Spoken Tutorial Project is funded by MHRD, Government of India.
	This is Himanshi Karwanje from IIT-Bombay. Thank you for joining.

Contributors and Content Editors

Karwanjehimanshi95, Madhurig, Snehalathak