For 3 hours i was blankly staring at my notes cause it was not making sense and the fact that i understood in less in 13 min is crazy. Sir, you are doing God's work
Man, these videos should be kept like a treasure to humanity... So amazing, with a wonderful connection to the real world! Honestly that is what I miss the most in my lecture notes... Why not talk about electric motors and TVs like Doc Schuster does? For an engineering student this is a gift that keeps on giving
You are absolutely incredible! I have spent three hours looking through textbooks and google trying to figure out how to solve this problem for my physics class and within 7 minutes of this video you have explained it all in a way that actually makes sense and allows me to solve this problem. Thank you thank you thank you!!!
You are the best professor ever. I struggled understanding the book and my professor in one hour cant do what you did in 12 minutes. Now I understand. Thank you!!!!
This was awesome. I mean it definitely helped me understand the whole concept of torque and current but the sound effects..those were the best. Haha thanks! :)
@@DocSchuster Which of the following is not a guaranteed way to increase the average torque produced on a loop carrying current? Increase the length of the loop Increase the number of turns Increase the torque angle Increase the breadth of the loop
You are so so passionate when you teach and it makes it so much easier to learn. I have managed to learn '10 lectures' worth of Electro Magnetics in under 4 hours with your videos. Thanks so much keep up the awesome work :)
Thank you for inadvertently explaining to me why we say that the current flows out of the positive terminal. I was always confused because I knew that only electrons could move through a wire but you showed me that the current of electrons IS actually flowing against the "current" in the circuit
OMG I have not words to use to thank you for this video, anything would be not enough. But I just going to say it any ways YOUR VIDEO IS AWESOME, THANK YOU SO MUCH FOR THE DYNAMIC EXPLANATION!!!!! YOU ROCK!!!!!!!!
a little confused. read that you find n^ (or area vector) by the right hand rule.... in this case by curling your fingers along the direction of the current...... then your thumb points in the direction of the area vector. if this is so, then the area vector would be pointed in and not out? (referring to 7:03)
I'm pretty sure it does just because he wanted it that way. Because the area vector is the cross product between width and length, you can make the area vector either point out of the page perpendicular to the surface, or into the page perpendicular to the surface, depending on what order you cross multiply the vectors. Additionally, choosing to have the area vector point into the page still illustrates his point that the magnitude of torque is maximized when the area vector points perpendicular to the magnetic field.
Great video! I was wondering, when, let's say, the loop has rotated around 45 degrees. Now would there not be an EXTRA 2 forces on the horizontal wires because you have now offset their angle from the magnetic field by 45 degrees (up and down)? It wouldn't affect much as long as the wires had a good bending resistance but still.
If we split the circuit in half down the spindle and had a top view, the horizontal wires would have an inward force for the half left of the spindle and outwards on the right half. Cool I hope I got that right
Uk i almost give up on physics but then never thought that learning from utube makes me easier to understand ahhh thankyou so much for thiss may God bless u. xoxo from a malaysian student
Absolutely. But not until 1879 was that a problem. My students often ask me why we don't just change the direction of conventional current. In the US, we're still using feet and teaspoons to measure stuff like it's 1612. Dang it.
Hi, why wouldn't we consider the centripetal force that acts till we reach the axis of rotation, in that case shouldn't we integrate over width from 0 to w/2?
Great video! I understood it till the part where you explained the forces for top view but got confused with the direction for rotation . Why would it stop after turning 90° and try to come back in the opposite direction ? please help
I had never heard of the passive sign convention. Sounds like a great way to get away from the vector nature of these torques. You're right, though, I am glossing over the details in this introduction. I think I did use the RHR a bit...
for the force that is out of the page , why do u use ur left hand to find the force. ? why didn't u use the right hand rule? and why did u use the in term of electrons and not the current? i'm very confused
try a magnetic fluid current loop Ev = B * core_length * v I = Ev / R P = I^2*R P = (B * l * v)^2 / R ==== use it in a toroid of cyclotron like coils magnetic fluid in a plastic tube loop sheathed with copper wire coils thanks for the memories of physics class ! CERN tries to prove the universe = High Voltage I'm trying to use a cyclotron to power a nation city or house
If a current passes through the coil shouldn't it induce a magnetic field on presence of already existing magnetic fields ( the green like that you drew )
Hey, I have a question. Indeed the torque will cause the closed loop wire to rotate, then go past its equilibrium point (where A vector points in the same direction as B) due to its inertia, and so it would rotate in the opposite direction back to the equilibrium point. How does this work for an AC Generator I have been looking for explanations everywhere, and all of them simply assume that the wire turns completely under the influence of the B field. Hope someone can clear my questions.
torque is the rotational motion produced on a fixed axis due to equal and opposite forces exerted by an external agency on the diametrically opposite ends of a body. In this case force is directed upwards on one part of the wire and downwards on the opposite part.
+Chhaya Arora Torque is basically a force that is moving/ rotating around something/object from a distant r=distant between them. Think of the solar system, where Earth is moving from a force exerted by Sun's gravitational pull from a distant of some million mile way. So Earth is experiencing a Gravitational torque from the Sun. I guess see some video about angular momentum to see what forces (torque) could do and if that is helpful.
Didn't you use your left hand to determine the force the first time? I think you did. Because when using the right hand, it doesn't give the same direction to the force.
He used his left hand because he was talking about the flow of the electrons, which is opposite to the flow of current. If you match the right hand rule to the direction of the arrow on the wire you'll see that your right thumb goes into the page as well. RH rule for current, LH rule for electrons.
I think your thinking about area vector is wrong. Because as current flows clockwise, the area vector is going to be into the page using the Corkscrew rule. But u said at 7:02 , that it points out of the page. If someone have better explanation, please let me know.
Why does one of my textbooks say t=Fd sin theta, while another one says that t=nBIA cos theta? I understand how it is BIA, but do not understand why one is sin and the other one is cos!
Excellent tutorial However this seems true for scalars, but not for vectors I assume we all agree that Torque = (Force = current Height X B) X Width However in general (Height X B) X Width doesn't= (Area = Height X Width) X B because vectors in a triple product are not commutative like scalars in multiplication Therefore in general Torque doesn't= [u = current (Area = Height X Width)] X B Pls point out my fallacy, I would love to use this on electric motors theory. Thks TomB
Tom Bouie I figured it out; It's important to note the relative orientation of the Wide, Height, & B field to the spinning rectangle current loop Although Wide&B are not in general perpendicular ; (current Height) & B and (current Height) & Wide are always perpendicular Torque= Wide x (Force= current Height x B) = (Wide dot B) current Height - [(Wide dot current Height)=0] B Torque= (current Area = Wide x current Height) x B = (Wide dot B) current Height - [(current Height dot B)=0] Wide Therefore Torque= Wide x (current Height x B) = (current Area) x B = (Wide dot B) current Height Note (current Height) & B or (current Height) & Wide not being perpendicular doesn't apply to this particular situation at all Thks for the video, TomB
there would be phase cancellation that would (depending on the proximity) would increase double or half the magnetic field. there is 90° that the phase can intersect without problem.
You bet man. I don't think I'll ever get tired of knowing that I've helped someone. Keep rocking and help someone else!
For 3 hours i was blankly staring at my notes cause it was not making sense and the fact that i understood in less in 13 min is crazy. Sir, you are doing God's work
I just came here for the sound effects. ;)
Oh, I love those funny sounds too.
Man, these videos should be kept like a treasure to humanity... So amazing, with a wonderful connection to the real world! Honestly that is what I miss the most in my lecture notes... Why not talk about electric motors and TVs like Doc Schuster does? For an engineering student this is a gift that keeps on giving
You are absolutely incredible! I have spent three hours looking through textbooks and google trying to figure out how to solve this problem for my physics class and within 7 minutes of this video you have explained it all in a way that actually makes sense and allows me to solve this problem. Thank you thank you thank you!!!
I know that you are probably tired of hearing this over and over again. But this video really helped me out a lot. Thanks mate
You are the best professor ever. I struggled understanding the book and my professor in one hour cant do what you did in 12 minutes. Now I understand. Thank you!!!!
6 years later now. My professor can’t do this either. Why didn’t he just learn how to teach well from videos like this?
This was awesome. I mean it definitely helped me understand the whole concept of torque and current but the sound effects..those were the best. Haha thanks! :)
hi
This is a 10 yr old video but it still works like a charm! Thank you sir!
If you were my professor of my physics class i would fall in love with physics!
XxKmCxXPR DO IT ANYWAY! Physics is great.
@@DocSchuster Which of the following is not a guaranteed way to increase the average torque produced on a loop carrying current?
Increase the length of the loop
Increase the number of turns
Increase the torque angle
Increase the breadth of the loop
@@shrungarpatil3076 is it option c
You are absolutely incredible! I have spent close to three hours looking through various physics text books and go
Why would the area vector be up at 6:54? Shouldn't you use the right hand rule with the current? That would have it pointing into the page....
You are so so passionate when you teach and it makes it so much easier to learn. I have managed to learn '10 lectures' worth of Electro Magnetics in under 4 hours with your videos. Thanks so much keep up the awesome work :)
Thank you so much for the lesson. Really easy to understand the way you explained it, specially with the sound effects. Phew phew.
Thank you for inadvertently explaining to me why we say that the current flows out of the positive terminal. I was always confused because I knew that only electrons could move through a wire but you showed me that the current of electrons IS actually flowing against the "current" in the circuit
OMG I have not words to use to thank you for this video, anything would be not enough. But I just going to say it any ways YOUR VIDEO IS AWESOME, THANK YOU SO MUCH FOR THE DYNAMIC EXPLANATION!!!!! YOU ROCK!!!!!!!!
"currents going that direction Phew phew phew *unintelligible*" 😂😂😂
a little confused. read that you find n^ (or area vector) by the right hand rule.... in this case by curling your fingers along the direction of the current...... then your thumb points in the direction of the area vector. if this is so, then the area vector would be pointed in and not out? (referring to 7:03)
Sound effects were* amazing too!!
One more amazing way of explaining physics...☺️
Love the way you interpret this!!!!!!!Thanks a lot!!!
how do we know the area vector points out at 6:55?
I'm pretty sure it does just because he wanted it that way. Because the area vector is the cross product between width and length, you can make the area vector either point out of the page perpendicular to the surface, or into the page perpendicular to the surface, depending on what order you cross multiply the vectors.
Additionally, choosing to have the area vector point into the page still illustrates his point that the magnitude of torque is maximized when the area vector points perpendicular to the magnetic field.
Great video! I was wondering, when, let's say, the loop has rotated around 45 degrees. Now would there not be an EXTRA 2 forces on the horizontal wires because you have now offset their angle from the magnetic field by 45 degrees (up and down)? It wouldn't affect much as long as the wires had a good bending resistance but still.
Noah P You're totally right. Is that force on the inward or outward (defined by the loop)?
It depends on CW or CCW rotation!
If we split the circuit in half down the spindle and had a top view, the horizontal wires would have an inward force for the half left of the spindle and outwards on the right half. Cool I hope I got that right
Uk i almost give up on physics but then never thought that learning from utube makes me easier to understand ahhh thankyou so much for thiss may God bless u. xoxo from a malaysian student
you put lots of effort in this topic to let us understand this.
Why in the world are the electrons flowing down if the current is flowing up? 1:37
+pinkfloydcookie BECAUSE CURRENT IS DEFINED AS THE MOTION OF POSITIVE CHARGES!
😂
Made me fall in love with Physics.Again.
you really explained very well to catch every point.
Absolutely. But not until 1879 was that a problem. My students often ask me why we don't just change the direction of conventional current. In the US, we're still using feet and teaspoons to measure stuff like it's 1612. Dang it.
at 1:44, does he use his "left" hand?? or right hand??
Even after 10 years this video helped me to ace my physics midterm
Hi, why wouldn't we consider the centripetal force that acts till we reach the axis of rotation, in that case shouldn't we integrate over width from 0 to w/2?
In my book, the final formula for torque has a cos in it. Isn't torque a cross product, shouldn't there be a sin?
You've got the wrong book I think!
Ends up you take an integral to derive that equation, so the sin flips to a cos. Dot product for specifically magnetic torque.
Amazing explanation but I am confused with rule you are using to determine direction of force
Great video! I understood it till the part where you explained the forces for top view but got confused with the direction for rotation . Why would it stop after turning 90° and try to come back in the opposite direction ? please help
Uddhov Harrit Make a 3D model that you hold in your hand and look what happens if you rotate it 180 degrees.
you explained this amazingly! thank you so much :D your videos are literally saving my degree lol
Can someone please explain to me how at 10:14 the left side is out of and the right side is inward? I thought it would be the opposite :/ plz help
your explanation is absolutely awesome!!
thanks for such a nice video
love your way of teaching
The area vector would be pointing into the page no>?
Great video 👍👌👌
I had never heard of the passive sign convention. Sounds like a great way to get away from the vector nature of these torques. You're right, though, I am glossing over the details in this introduction. I think I did use the RHR a bit...
I love the color-coded diagrams it really helped me sort things in my brain! Thank you!
12:30 what causes the current change?
Love the different loops! :D
At 6:40, why is there no torque?
nice one doc...............
what's the direction of net torque acting on the loop?
1:44 you're using your left hand,the direction would be out of the screen..correct me,if I'm wrong.!
it is right
for the force that is out of the page , why do u use ur left hand to find the force. ? why didn't u use the right hand rule? and why did u use the in term of electrons and not the current? i'm very confused
So it doesn't rotate? It just go straight to the axis of rotation back to its original position?
What the hell was that? ...u just forced me to subscribe. Amazing...
👌👌👌👌
Awesome! thanks professor!
lol just cracked my fingers using the three finger salute rule.
You have to measure and amplifie the signal.
Or construct a feedback mechanism.
why have u used left palm for electrons and right palm for protons??/answer please..
Do you create a generator with an alternating current?
Solid explanation.
You are a godsent gift to me! Thank you so much for explaining this to me!
try a magnetic fluid current loop
Ev = B * core_length * v
I = Ev / R
P = I^2*R
P = (B * l * v)^2 / R ==== use it in a toroid of cyclotron like coils
magnetic fluid in a plastic tube loop sheathed with copper wire coils
thanks for the memories of physics class !
CERN tries to prove the universe = High Voltage
I'm trying to use a cyclotron to power a nation city or house
What about the magnetic potential energy in both the cases?
Mv Dk I TOO HAVE A DOUBT ABOUT IT. COULD SOME ONE HELP ME OUT?
I wish you were my physics teacher then it would always be fun to study physics
How did you find the direction of the force on the sections of wire ? :?
no worries understood...! u teach gr8. :D
If a current passes through the coil shouldn't it induce a magnetic field on presence of already existing magnetic fields ( the green like that you drew )
So what is the game changer that you are talking about at the end of the video?
a motor!!
Grafiore an AC motor?
Or starters at cars!
Or inside of the cars!
How is there no net force? Is it because there are equal and opposite forces on the two vertical parts of the coil?
Anika Agrawal Yep! Cancellation!
Hey, I have a question. Indeed the torque will cause the closed loop wire to rotate, then go past its equilibrium point (where A vector points in the same direction as B) due to its inertia, and so it would rotate in the opposite direction back to the equilibrium point. How does this work for an AC Generator I have been looking for explanations everywhere, and all of them simply assume that the wire turns completely under the influence of the B field. Hope someone can clear my questions.
"Tssssss" "Shhhhhhhhh" hahahaha love it!
How to calculate the Revolution Per Minute (RPM) of the coil?
n that happens in the alternator or the generator , the direction of current is reversed after every half cycle .!!!!! amazing video!!! thanks
That was a funny video , I liked it
HOW DO YOU FIGURE OUT THE ROTATION? (Pardon the caps lock; Also, I still don't understand what exactly torque is?)
Chhaya Arora I've got a video on torque that might help! I presume some comfort with rotations at this point.
torque is the rotational motion produced on a fixed axis due to equal and opposite forces exerted by an external agency on the diametrically opposite ends of a body. In this case force is directed upwards on one part of the wire and downwards on the opposite part.
+Chhaya Arora Torque is basically a force that is moving/ rotating around something/object from a distant r=distant between them. Think of the solar system, where Earth is moving from a force exerted by Sun's gravitational pull from a distant of some million mile way. So Earth is experiencing a Gravitational torque from the Sun. I guess see some video about angular momentum to see what forces (torque) could do and if that is helpful.
This man made a motor!
This was exactly what I needed, thank you so much! I've been looking for a vid about this and this perfectly matches my assignment
Didn't you use your left hand to determine the force the first time? I think you did. Because when using the right hand, it doesn't give the same direction to the force.
same
Elisabeth Emane Was I considering a negative charge?
He used his left hand because he was talking about the flow of the electrons, which is opposite to the flow of current. If you match the right hand rule to the direction of the arrow on the wire you'll see that your right thumb goes into the page as well. RH rule for current, LH rule for electrons.
Great Video Man
Very good video.
what if the magnetic field is going into the paper what would be the direction of the torque ??
Brilliant sir
Sir u are using right hand rule to find force. We have to use the left hand rule so your results are exactly opp to that i found
great explanation!!!
Great Video. Thank you
THat was so well explained :D
Is the net magnetic force on the loop is 0?
sir ,can we use cos theta intead of sin
I think your thinking about area vector is wrong. Because as current flows clockwise, the area vector is going to be into the page using the Corkscrew rule. But u said at 7:02 , that it points out of the page. If someone have better explanation, please let me know.
Why does one of my textbooks say t=Fd sin theta, while another one says that t=nBIA cos theta? I understand how it is BIA, but do not understand why one is sin and the other one is cos!
Since the force is at a right angle to the current, theta in one equation is the complement of theta in the other equation.
Finally, finally! I FOUND A SATISFYING EXPLANATION!
Excellent! thanks a lot!
yo my dude, you used your left hand for the RHPR at 2:00
This was an incredible video! Thank you so much :D
Hybrit Current Motors:
Direct Current causing a movement in a coil driven by a weak (or strong?) alternated current (Y) !
Excellent tutorial
However this seems true for scalars, but not for vectors
I assume we all agree that Torque = (Force = current Height X B) X Width
However in general (Height X B) X Width doesn't= (Area = Height X Width) X B
because vectors in a triple product are not commutative like scalars in multiplication
Therefore in general Torque doesn't= [u = current (Area = Height X Width)] X B
Pls point out my fallacy, I would love to use this on electric motors theory.
Thks TomB
Tom Bouie
I figured it out;
It's important to note the relative orientation of the Wide, Height, & B field to the spinning rectangle current loop
Although Wide&B are not in general perpendicular ;
(current Height) & B and (current Height) & Wide are always perpendicular
Torque= Wide x (Force= current Height x B)
= (Wide dot B) current Height - [(Wide dot current Height)=0] B
Torque= (current Area = Wide x current Height) x B
= (Wide dot B) current Height - [(current Height dot B)=0] Wide
Therefore Torque= Wide x (current Height x B) = (current Area) x B
= (Wide dot B) current Height
Note (current Height) & B or (current Height) & Wide not being perpendicular doesn't apply to this particular situation at all
Thks for the video, TomB
This was great thank you!
how to determine the angle ?
Do partial differential equation videos please
what if a loop is at an angle to the magnetic field?
the vector A in x not dot becasue its inside the page
What would happen if the horizontal branches were not parallel to the magnetic field?
+more fabulous than Yu There would be forces on them!
The moon would crash earth XD
My Name what the...!?
😂😂😂😂
there would be phase cancellation that would (depending on the proximity) would increase double or half the magnetic field. there is 90° that the phase can intersect without problem.
Ok, so how do we keep changing the direction of current? Instead of a direct current why can't we use alternated current?....btw awesome video!
Mihir Kavishwar ...That's exactly what I was hoping you'd notice!!!!