If i have gotten anywhere in IB Physics, it's only thanks to you. My teacher is school is hopeless and well you are amazing. He is really funny in the way he explains things, giving us questions before any confidence in the concept. However your methodology of explaining is excellent. You are the reason that I am doing well. Thank you ever so much. I know watch your videos and do well in class.
At 1:46 I had already included the number of turns in the overall flux linkage. As far as the minus sign is concerned, yes. I make that clearer at 7:10 where I introduce Lenz's law.
Yes. Its the left hand rule for a motor and right hand for a generator (ie induced current). Please let me know what time on the video I say otherwise and I will add an annotation to correct it.
9 years later and still helping students..it's called timeless...I have just found out about your channel and as I am exploring, I am finding great contents that I think really gonna help me..thank you
I assume you mean the one which reads "A horseshoe magnet is placed on a balance. A stiff metal wire is clamped horizontally between the poles, as illustrated in Fig. 5.1." The point is that the stiff metal wire is clamped and cannot move. So the force will result in the magnet moving. You are given the value of the current, the relevant length of wire and the force (tho you need to convert to Kg). Use F=BIl to find B. Use LH rule for direction.
Hayqa Hassan - Normally positive and negative particles would attract. (like charges attract and unlike charges repel). Is there a specific instance you are thinking of?
Thanks. I had already put in an annotation at 15:48 to that effect to point out that the current will actually flow the opposite way to the way shown in the diagram. I understand that not everyone can see the annotations, sadly, but it's the only way I know of to make corrections or clarifications once the video is uploaded.
Just something to remember -It is denoted BAcos(theta) where theta is the angle made by the wire with the normal of the current, if theta=0 then it cuts the maximum number of field lines if theta=90 it cuts zero field lines.
Yes. Power is VI. Power loss is also VI but relates of course to the V and I associated with the part of the circuit where the power loss occurs. Since V=IR you can say that power loss is V^2/R or I^2 R. The latter is more generally used. But if you use V^2/R you must make sure you identify the potential difference (voltage) across the component or cable in which the power loss arises.
If I have understood the question correctly, the answer is B. If the loop is perpendicular to the magnetic field vendettas say that the magnetic field goes from left to right the current goes into the paper and the forces will be downwards. But at the bottom of the loop the force will be upwards. There is no torque. But this largely depends on me having understood the problem without a diagram.
If the coil is parallel at t=0 there will be no induced emf. This is a startup effect and its only when the system has got going that you see the emf lagging behind.
Well when the loop is in the field such that the angle between the loop and the field is zero, no flux goes thro the loop (since it is edge on). That is achieved with BAN sin 0 = 0.
Finally explained well. 3.30 - My Book just doesn't go over the fact that it is the applying of the Force (with respect to the Bar Magnetic Field) which can induce a current in the wire. I wish they explained things better, it would save plenty of hassle.
The answer is that the induced emf is said to lag behind. Clearly when there is no flux passing through the coil it cannot generate an emf. What happens is that when the coil is at right angles to the flux, there will be an induced current in the wire. But it will take time to build up. It just so happens that (in theory) by the time the induced voltage has reached its peak (because of the lag) the coil will have rotated thro 90 degrees.
Your vids are very clearly presented. I'm wondering if you have one, a vid, explaining the relationship between Phi B and magnetic filed intensity H. Its the H I cant grasp What is it .?
The first circuit consists of an inductance coil and a source of power in this case alternating voltage. The second circuit is an entirely separate circuit which just contains an inductance coil.
A transformer consists or two coils of wire (primary and secondary). An alternating current in the primary will produce a varying magnetic field. Faraday's law says that the emf induced in the secondary is proportional to the rate of change of flux produced by the primary.
You might best remember it as right hand rule for generators and left hand rule for motors. Or right hand rule where the current is induced. So in the case of a motor we drive a current thro a wire in the presence of a magnetic field. The LH rule tells us how the wire will move in the field. In the case of a generator we move a wire in a magnetic field and this induces a current to flow in the wire. The RH rule determines which direction the current will flow.
Yes it does. The EMF and hence the current is proportional to the rate of change of flux, so the faster the coil rotates the greater is the rate of change of flux.
It may be that the angle is differently defines. I define theta as the angle between the plane of the coil and the magnetic field. your text book may define the angle as between the NORMAL to the plane and the mag field.
I had the question: 'An aircraft, of wing span 60m, flies horizontally at a speed of 150ms^-1. If the vertical component of the Earth's magnetic field in the region of the plane is 1.0 x 10^-5T what is the magnitude of the magnetic flux cut by the wings in 10s?' typed out, about to ask for help, but then i realized it was more or less exactly the same as your experiment at 05:15. Thank you so much, even my teacher couldn't answer that question
The voltage is proportional to the rate of change of flux. So its a question of how fast it is changing. When the flux is at its maximum (ie when the magnetic field lines are perpendicular to the plane of the loop) the rate of change is actually very small. Ditto when flux is zero. Rate of change is maximised when loop is midway between max and min position. See also my response to badshabz1 below for analogy with rate of change of daylight.
A circular loop of thin wire is placed so that its plane is perpendicular to a magnetic field as shown. (Just single loop of wire perpendicular to a magnetic field carrying a current clockwise) As the switch is closed, the loop of wire will A become a circle of smaller radius. B not change. c rotate about its centre. D rotate so that its plane is parallel to the field.
Well the voltage is equal to the rate of change of flux. So its not the amount of flux but the amount by which it is changing. When the flux is at its maximum or minimum its rate of change is very small. At its mid-point it has maximum rate of change. Think of how the length of days changes throughout the year. On Dec 21 and Jun21 when the day length is min or man the actual rate of change very small. On Mar 21 and Sept 21 when day length at mid-point, the rate of change very large - 15 mins/wk.
I have a question. When we say that a change in magnetic flux induces a voltage in another wire or circuit, where is the potential difference? Voltage is a potential difference between 2 points. Which 2 points are we looking at? Across each end of the coil? 2 other random points in the circuit? In the example you give around 4:45. I understand that current is related to voltage via Ohm's Law--so if you have an induced current you would by pure mathematical grounds have an induced voltage, sure. But I'm having a hard time connecting this to how voltage is rigorously built up in textbooks as being the difference in potential between 2 points in space. Is there a build up of charge density somewhere in the circuit with the ammeter? Where would you place the two leads of a voltmeter to detect the induced potential difference?
Referring to what you said about transformers stepping up and down the voltage in the transmission cables, isn't there an equation P=(V^2)/R? And if the cable has a fixed resistance, isn't power loss proportional to voltage square? I would be delighted if you respond to this question very soon as my Unit 4 Physics exam is the day after tomorrow and I think that you can deduce from this question that my preparation is extremely poor. Thanking you in advance! PS. I just love the way you teach!
From around 20:49 you mention how the Flux Linkage is 90 Degrees out of Phase with the Induced Voltage, I understand the maths behind it, by why is this the case? Why would you get maximum emf induced when there is no flux cutting the conductor? Is this just a physical phenomenon because of how nature works? Secondly if this is the case, then initially if the conductor is parallel at time 0, will the emf induced still be at a maximum if no flux linkage has passed through yet?
I've avoided doing Maxwell's equations because I could never better the excellent series on Electricity and Magnetism (which inter alia derive the Maxwell equations) by Prof Walter Lewin of MIT. If you Google his name you should get the UA-cam address. I can wholly commend the entire series.
+Greg Brewster Flux is not the field strength per unit area, field strength (flux density) is the flux per unit area. Hence Flux is B.A (field strength multiplied by area), not B/A.
Step-up transformers are used at power stations to produce the very high voltages needed to transmit electricity through the National Grid power lines. These high voltages are too dangerous to use in the home, so step-down transformers are used locally to reduce the voltage to safe levels.
Perhaps maximum voltage (at end of video) as induced magnetic field (in the wire) discharges most when at right angles to the flux from the magnetic field??
hope you are well sir, i was hoping you could explain why the flux linkage and the voltage are out of phase without using calculus as we dont do this in physics. Thanks great videos!!
Thank you for the video. One thing, I think the earths field is backwards. The "north" pole is actually magnetic south pole. The other thing is, can you fill us in on the units? What is B measured in? I am thinking about building an alternator and I am trying to tie together the strength of the magnets, the size of the coils, and the speed of rotation for a given output.
Quite right. Because the north pole of a magnet points to the “north” pole of the Earth, that must actually be a South Pole. Magnetic field,B, is usually measured in Tesla.
Please could you go into more detail as to why the field strength per unit area is given by BA as if field strength is B surely dividing it by unit area (rather than multiplying) would give "the field strength per unit area". Thanks!
Also, 11:38, I don't understand how flux "changes". You said Flux is just BAn, right? So, the area isn't change, the number of coils isn't changing, the magnetic field isn't changing (I'm guessing, at least you never mentioned that). Are you saying the magnetic field changes by a current being run through the wire? Does that turn the north to south and south to north? How is flux "changing"? OR is somehow the magnet remaining stationary, the are and number of coils in the solenoid staying stationary, and the current being run through the wire somehow having an effect on the magnetic field? And if so, can you expand on what exactly that means? Or are you saying running a current through a solenoid generates a magnetic field?
At 9:32 when you are moving a wire through a static magnetic field; I think it makes more sense to think of it like this: When you move the wire down, that downward motion is actually a current through the field. This generates a force on the electrons in the wire to the left, inducing current. that induced current interacts wit the field generating an opposing force to the force you are exerting on the wire. is that a correct way of looking at this?
Yes, but it's much lower than I^2xR, so you'd rather have a high voltage than a high current, as with voltage you divide by R, and current you multiply by R
thank you very much sir. your's all video are excellent. it helping me a lot in my exam and also inspried me in physics . sir, can u make on a video Steady current Ohm’s law - Differential form, Kirchoff’s Law; Wheatstone bridge - its sensitivity (qualitative discussion only). sorry for my bad english.......
Hello, these videos are great for revision, but one small error (I think) is with the equations at the end; unless I'm mistaken the equation for flux linkage should use cos and the equation for induced emf should use sine? I checked my data/equations sheet from the exam board and that uses sine for emf and cos for flux linkage although I might have missed something.
Sir, I've a question when a beam of positive charges and a beam of negative charges go parallel to each other then would they attract each other or repel each other? i have studied that when two isolated but opposite charges in motion come across each other they repel each other rather than attraction similar is the case with two similar charges in motion they attract each other rather than repulsion.But here is beam of proton and electron so i don't understand that weather i should take it as conventional and electronic current or charges in motion.and if i take the electron beam as flow of electrons then does the direction of current will be opposite to electron flow or in the direction of electrons as electronic current. please help me.THANKS
is there a cure for electomagatisum in the body? I have too much electomagnetism and it is very hard to live, day to day llife is very painful and drinking water and takning a shower is deadly because of pulling all the metal to the water on the my body, in turn making me more magnetic...help or I will die
If i have gotten anywhere in IB Physics, it's only thanks to you. My teacher is school is hopeless and well you are amazing. He is really funny in the way he explains things, giving us questions before any confidence in the concept. However your methodology of explaining is excellent. You are the reason that I am doing well. Thank you ever so much. I know watch your videos and do well in class.
thesmellofnewpages I misread that as "my teacher in school is homeless" XD
Najey Rifai lol 😂
Thanks a for making these videos - you have no idea how helpful they were.
Thanks. I'm always grateful when errors are pointed out. It enables me to make annotations to clarify.
At 1:46 I had already included the number of turns in the overall flux linkage. As far as the minus sign is concerned, yes. I make that clearer at 7:10 where I introduce Lenz's law.
Yes. Its the left hand rule for a motor and right hand for a generator (ie induced current). Please let me know what time on the video I say otherwise and I will add an annotation to correct it.
DrPhysicsA hi why do we use the right hand rule for a generator ?
I have been looking for a channel like this that explains the equations behind all of the physics for so long! THANK YOU SO MUCH!
maybe its the accent that makes this video so conducive for learning
"Does it induce a current? Yes it does! It's called an induced current!" HAHAHA that made my day! Thanks!
Your videos should be included on a DVD with all revision books, great clear descriptions, Thanks.
you're so much better than my teacher at school. Now i just need a DrChemistryA :)
I have my phy 4 exam in precisely 1 and a half hours.. Wish I saw this video earlier.. it helps soo much thank you!!
How'd it go? :)
@@muhammadshayanusman5540 dude it’s been six years 😂😂😂
@@muhammadshayanusman5540 he's married now
9 years later and still helping students..it's called timeless...I have just found out about your channel and as I am exploring, I am finding great contents that I think really gonna help me..thank you
I assume you mean the one which reads "A horseshoe magnet is placed on a balance. A stiff metal wire is clamped horizontally between the poles, as illustrated in Fig. 5.1." The point is that the stiff metal wire is clamped and cannot move. So the force will result in the magnet moving. You are given the value of the current, the relevant length of wire and the force (tho you need to convert to Kg). Use F=BIl to find B. Use LH rule for direction.
appreciate your work on youtube! Don't understand a word during the lessons but when I go too your chanel everything just light upp
Your lessons have helped me with my designs drastically! Thank you so much! :)
Hayqa Hassan - Normally positive and negative particles would attract. (like charges attract and unlike charges repel). Is there a specific instance you are thinking of?
Thanks. I had already put in an annotation at 15:48 to that effect to point out that the current will actually flow the opposite way to the way shown in the diagram. I understand that not everyone can see the annotations, sadly, but it's the only way I know of to make corrections or clarifications once the video is uploaded.
Just something to remember
-It is denoted BAcos(theta) where theta is the angle made by the wire with the normal of the current, if theta=0 then it cuts the maximum number of field lines if theta=90 it cuts zero field lines.
Yes. Power is VI. Power loss is also VI but relates of course to the V and I associated with the part of the circuit where the power loss occurs. Since V=IR you can say that power loss is V^2/R or I^2 R. The latter is more generally used. But if you use V^2/R you must make sure you identify the potential difference (voltage) across the component or cable in which the power loss arises.
If I have understood the question correctly, the answer is B. If the loop is perpendicular to the magnetic field vendettas say that the magnetic field goes from left to right the current goes into the paper and the forces will be downwards. But at the bottom of the loop the force will be upwards. There is no torque. But this largely depends on me having understood the problem without a diagram.
If the coil is parallel at t=0 there will be no induced emf. This is a startup effect and its only when the system has got going that you see the emf lagging behind.
Well when the loop is in the field such that the angle between the loop and the field is zero, no flux goes thro the loop (since it is edge on). That is achieved with BAN sin 0 = 0.
Finally explained well. 3.30 - My Book just doesn't go over the fact that it is the applying of the Force (with respect to the Bar Magnetic Field) which can induce a current in the wire. I wish they explained things better, it would save plenty of hassle.
The answer is that the induced emf is said to lag behind. Clearly when there is no flux passing through the coil it cannot generate an emf. What happens is that when the coil is at right angles to the flux, there will be an induced current in the wire. But it will take time to build up. It just so happens that (in theory) by the time the induced voltage has reached its peak (because of the lag) the coil will have rotated thro 90 degrees.
My teacher couldn't explain lenz no matter what, he'd confuse us all with a right hand rule for inductions.... this is the best explanation
Your vids are very clearly presented.
I'm wondering if you have one, a vid, explaining the relationship between Phi B and magnetic filed intensity H.
Its the H I cant grasp
What is it .?
The first circuit consists of an inductance coil and a source of power in this case alternating voltage. The second circuit is an entirely separate circuit which just contains an inductance coil.
A transformer consists or two coils of wire (primary and secondary). An alternating current in the primary will produce a varying magnetic field. Faraday's law says that the emf induced in the secondary is proportional to the rate of change of flux produced by the primary.
You might best remember it as right hand rule for generators and left hand rule for motors. Or right hand rule where the current is induced. So in the case of a motor we drive a current thro a wire in the presence of a magnetic field. The LH rule tells us how the wire will move in the field. In the case of a generator we move a wire in a magnetic field and this induces a current to flow in the wire. The RH rule determines which direction the current will flow.
Yes it does. The EMF and hence the current is proportional to the rate of change of flux, so the faster the coil rotates the greater is the rate of change of flux.
It may be that the angle is differently defines. I define theta as the angle between the plane of the coil and the magnetic field. your text book may define the angle as between the NORMAL to the plane and the mag field.
I had the question:
'An aircraft, of wing span 60m, flies horizontally at a speed of 150ms^-1. If the vertical component of the Earth's magnetic field in the region of the plane is 1.0 x 10^-5T what is the magnitude of the magnetic flux cut by the wings in 10s?' typed out, about to ask for help, but then i realized it was more or less exactly the same as your experiment at 05:15. Thank you so much, even my teacher couldn't answer that question
Haha 10 weeks at school crammed into 40mimutes. Cheers Doc!
The voltage is proportional to the rate of change of flux. So its a question of how fast it is changing. When the flux is at its maximum (ie when the magnetic field lines are perpendicular to the plane of the loop) the rate of change is actually very small. Ditto when flux is zero. Rate of change is maximised when loop is midway between max and min position. See also my response to badshabz1 below for analogy with rate of change of daylight.
I would suggest adding Eddy Currents and Homopolar Generator to the course if appropriate
A circular loop of thin wire is placed so that its plane is perpendicular to a magnetic
field as shown.
(Just single loop of wire perpendicular to a magnetic field carrying a current clockwise)
As the switch is closed, the loop of wire will
A become a circle of smaller radius.
B not change.
c rotate about its centre.
D rotate so that its plane is parallel to the field.
Sir you are wonderful !
Well the voltage is equal to the rate of change of flux. So its not the amount of flux but the amount by which it is changing. When the flux is at its maximum or minimum its rate of change is very small. At its mid-point it has maximum rate of change. Think of how the length of days changes throughout the year. On Dec 21 and Jun21 when the day length is min or man the actual rate of change very small. On Mar 21 and Sept 21 when day length at mid-point, the rate of change very large - 15 mins/wk.
You are a unsung hero.
You might like to see my video on Maxwell's equations which covers this in more detail.
Extraordinarily clear and masterfully planned , thank you!
I likes your way of teaching and explaining to understand the concepts
Thank you so much
probably the hardest thing in A2 physics
well explained..Sir!
These are great videos you really make physic more interesting you deserve an award. Thanks soo much!!!
Timestamps:
0:13 = Flux, Flux Density, Flux Linkage, Φ=BA(N)
1:52 = Induced Current
4:39 = Faraday's Law
6:58 = Lens' Law
9:48 = Transformers and alternating current
14:44 = Generators (and graphing induced emf)
Well actually, magnetic flux density is B (sometimes also called magnetic field. BA is called magnetic flux.
I have a question. When we say that a change in magnetic flux induces a voltage in another wire or circuit, where is the potential difference? Voltage is a potential difference between 2 points. Which 2 points are we looking at? Across each end of the coil? 2 other random points in the circuit?
In the example you give around 4:45. I understand that current is related to voltage via Ohm's Law--so if you have an induced current you would by pure mathematical grounds have an induced voltage, sure. But I'm having a hard time connecting this to how voltage is rigorously built up in textbooks as being the difference in potential between 2 points in space.
Is there a build up of charge density somewhere in the circuit with the ammeter? Where would you place the two leads of a voltmeter to detect the induced potential difference?
Referring to what you said about transformers stepping up and down the voltage in the transmission cables, isn't there an equation P=(V^2)/R? And if the cable has a fixed resistance, isn't power loss proportional to voltage square? I would be delighted if you respond to this question very soon as my Unit 4 Physics exam is the day after tomorrow and I think that you can deduce from this question that my preparation is extremely poor. Thanking you in advance!
PS. I just love the way you teach!
It is the Edexcel Unit 4 Junee 2011 Paper Question 2. Its on the Edexcel website but i cannot post links on here.
Sir.Dr.thankyou for your nice justification and explanation .
From around 20:49 you mention how the Flux Linkage is 90 Degrees out of Phase with the Induced Voltage, I understand the maths behind it, by why is this the case?
Why would you get maximum emf induced when there is no flux cutting the conductor? Is this just a physical phenomenon because of how nature works?
Secondly if this is the case, then initially if the conductor is parallel at time 0, will the emf induced still be at a maximum if no flux linkage has passed through yet?
Thank you so much - selflessness at its best!
I FINALLY GET LENZ'S LAW ILY
I've avoided doing Maxwell's equations because I could never better the excellent series on Electricity and Magnetism (which inter alia derive the Maxwell equations) by Prof Walter Lewin of MIT. If you Google his name you should get the UA-cam address. I can wholly commend the entire series.
Hello,
At 01:00 you mention the Flux is the field strength PER unit area. Why then is the equation Flux = B.A and not Flux = B/A?
+Greg Brewster B.A gives you the total flux.
+Greg Brewster Flux is not the field strength per unit area, field strength (flux density) is the flux per unit area. Hence Flux is B.A (field strength multiplied by area), not B/A.
How do you know when to use the left and hand and when to use the right hand rule?
Step-up transformers are used at power stations to produce the very high voltages needed to transmit electricity through the National Grid power lines. These high voltages are too dangerous to use in the home, so step-down transformers are used locally to reduce the voltage to safe levels.
beautiful.well done sir
at 8:24 should the induced current be in the left direction to oppose the downward force if the magnetic field goes into the paper??
Right hand rule for generators. Left hand rule for motors. In motor the electricity generates motion. In a generator the motion generates electricity.
if a magnet falls vertically downwards through a coil is there induced emf as the magnet travels within the region of the coil?
Yes because as the magnet falls there is a changing flux in the region of the coil.
Perhaps maximum voltage (at end of video) as induced magnetic field (in the wire) discharges most when at right angles to the flux from the magnetic field??
U R amazing Professor.!!! Thanks for sharing your knowledge..
And that would cause it to move down even more! Thanks for the vids
Thank God for your videos!
Thanks.
This has been an extreme help!
hope you are well sir, i was hoping you could explain why the flux linkage and the voltage are out of phase without using calculus as we dont do this in physics. Thanks great videos!!
Thank god for these videos! Great explanation,great job!!! Thanks :D
why is there an induced voltage when the coil isnt cutting any lines?
Thank you for the video. One thing, I think the earths field is backwards. The "north" pole is actually magnetic south pole.
The other thing is, can you fill us in on the units? What is B measured in?
I am thinking about building an alternator and I am trying to tie together the strength of the magnets, the size of the coils, and the speed of rotation for a given output.
Quite right. Because the north pole of a magnet points to the “north” pole of the Earth, that must actually be a South Pole. Magnetic field,B, is usually measured in Tesla.
hello sir, just wanted to say that at 05:14 doesn't the emf = - number of turns *the rate of change of flux?
thanks a loot...you are a great teacher
why is flux density equal to BA when it says magnetic field per unit area(b/a)?
Thank you so much
10:25 the solenoid is connected to "Anita"? What does the A mean? I'm kinda deaf, sorry
"A second coil of wire which has got an ammeter connected to it"
+DrPhysicsA Ammeter! Duh, thanks.
connected to "Anita", lmao
lol
XD
is it not right hand rule which is used with induced current
Please could you go into more detail as to why the field strength per unit area is given by BA as if field strength is B surely dividing it by unit area (rather than multiplying) would give "the field strength per unit area". Thanks!
Also, 11:38, I don't understand how flux "changes". You said Flux is just BAn, right? So, the area isn't change, the number of coils isn't changing, the magnetic field isn't changing (I'm guessing, at least you never mentioned that). Are you saying the magnetic field changes by a current being run through the wire? Does that turn the north to south and south to north? How is flux "changing"?
OR is somehow the magnet remaining stationary, the are and number of coils in the solenoid staying stationary, and the current being run through the wire somehow having an effect on the magnetic field? And if so, can you expand on what exactly that means?
Or are you saying running a current through a solenoid generates a magnetic field?
Sir, I think at 17:53 you have gotten the sin and cos mixed up.. i thought the flux = BAN COS wt (w=2piF) and the emf is e sin wt ?
At 9:32 when you are moving a wire through a static magnetic field; I think it makes more sense to think of it like this: When you move the wire down, that downward motion is actually a current through the field. This generates a force on the electrons in the wire to the left, inducing current. that induced current interacts wit the field generating an opposing force to the force you are exerting on the wire.
is that a correct way of looking at this?
I think that is right. But it is probably easier to remember and workout using the right or left hand rule.
sir, when voltage is high, power loss = (voltage)^2 / resistance.
its still high , right?
+Akshay Mohan long wire has lot of resistance (R) [I^2*R] > [V^2/R].
Yes, but it's much lower than I^2xR, so you'd rather have a high voltage than a high current, as with voltage you divide by R, and current you multiply by R
9:20 panicking ensues
Thanks teacher
Thankyou
Yes it is. Thank You.
Thanks
thank you very much sir. your's all video are excellent. it helping me a lot in my exam and also inspried me in physics .
sir, can u make on a video
Steady current Ohm’s law - Differential form, Kirchoff’s Law; Wheatstone bridge - its sensitivity (qualitative discussion only).
sorry for my bad english.......
Aren't 3-phase genaratrors mostly used in power stations? and How do they work?
can you explain more about how an ac current will cause changes in flux? i don't get it
Hello, these videos are great for revision, but one small error (I think) is with the equations at the end; unless I'm mistaken the equation for flux linkage should use cos and the equation for induced emf should use sine? I checked my data/equations sheet from the exam board and that uses sine for emf and cos for flux linkage although I might have missed something.
Do you get into special relativity with respect to induced current by magnetic fields in other videos?
This is what I stay awake to.
Sir, I've a question when a beam of positive charges and a beam of negative charges go parallel to each other then would they attract each other or repel each other? i have studied that when two isolated but opposite charges in motion come across each other they repel each other rather than attraction similar is the case with two similar charges in motion they attract each other rather than repulsion.But here is beam of proton and electron so i don't understand that weather i should take it as conventional and electronic current or charges in motion.and if i take the electron beam as flow of electrons then does the direction of current will be opposite to electron flow or in the direction of electrons as electronic current. please help me.THANKS
Good morning,
Can you suggest us something about induction magnetometers? I'm trying to learn something about these devices !
Thank you so much
can you do a video on electromagnetic waves and Maxwell's equations
can u explain the out of phase again
hi sir, thank you for posting these videos. do you have any videos for biot savart theory?
is there a cure for electomagatisum in the body? I have too much electomagnetism and it is very hard to live, day to day llife is very painful and drinking water and takning a shower is deadly because of pulling all the metal to the water on the my body, in turn making me more magnetic...help or I will die
emf = flux linkage/time.......right?
Minipaba Gunarathne change in flux linkage