Whenever I watch @KeithandBridget solution, it inspires me to do even better with my solution 🙂, Thankyou Keith And Thankyou professor for uploading this solution.
Thanks for the kind comment. 3 things I do that may help you. When I solve the problem I then put it aside and come back later and solve it again and check the two sets of answers agree. Second I watch the most relevant WL lecture I can find, 8.02 lecture 20 for this problem. Third I imagine explaining my answer to someone who has just watched the same lecture. Anyway I am glad I inspire you. This whole site is inspirational to me.
I agree, good explanation. A bit british maybe :-) ... Did you count my solution as correct or not ? I worked with the sub result and Keith expressed all current in R and V. Should I have done that ? Is it a requirement ?
You look veryvery good. I gave it up with Physics since Christmas. I hope, you will be my friend, as I'm yours, no matter what will seperate our lives. Could be, I will come back to Physics, because it is still my secret love.
Sir, I saw in a video that after rotating a rim wheel, you sat on a chair and the chair started rotating, but sir, in this situation all the force is internal and internal force never provides motion, then how did the chair start rotating?
Good morning sir, I have a question that in projectile motion, why only y- axis is taken for time of flight And why do not consider x axis for time of flight? I asked many teachers and professor but their answers are not satisfying.
Professor I’m solving your electricity assignments . Please give me some advice about problem solving. I’m preparing for JEE. ( yogurt doesn’t work for me , kindly give me helpful practical advice)
you have 2 options option 1: eat yogurt every day but *never on Fridays* That worked well for Einstein, also for me. option 2: Watch all my 94 MIT course lectures. Start with 8.01, then 8.02, then 8.03. Do all the homework and take all my exams. *I guarantee you that you will then do very well on the Physics portion of any freshman college or JEE exam* You will find all information you need on this channel in three playlists "Homework, Exam, SolutionsY & Lecture Notes". 8.01 & 8.02 will each take about 200 hours, 8.03 about 250 hours.
A long current-carrying wire, with no closed loop, would be accumulating a charge at one end, and the opposite charge at the other end. If it is carrying a steady current, the charge would be growing at a constant rate. There'd still be a transient electric field immediately at the end of the current-carrying wire, due to the charge build-up. Ampere's law would still apply, you'd just be measuring a magnetic field of displacement current, instead of current.
Think I see where you may be going with this professor, unless my imagination is playing tricks on me😉-🦅- Sorry about the high school physics - I didn't like the teacher and couldn't see the value in a lot of the work back then🤣 Will try harder when I have the time. Sabine Hossenfelder did a shorts video on the 5 most difficult physics problems if you want to have a look at it - I thought it was extremely helpful although could be wrong😅
I guess part c) is wrong. I1 = 0, I2 = I3 = (U - R1*I)/R3 with I := U / (R1 + R2*R3/(R2+R3)) (I = same current like I1 in part b or I3 is the same current as I3 in part b) The energy is stored in the magnet field of the coil and the coil is then the battery, that means the current flows from one side of the coil through R3, then through R2 and then to the other side of the coil. So the direction of the current I2 must be the same direction of I3 and not I2 = -I3.
@@lecturesbywalterlewin.they9259 I understand what you mean. If you draw R2 on the same height as R3 right beside R3 the same current would flow through both resistors in the same direction (for the case c)).
The current in I3 does not change direction when the switch is opened. So the current in I2 must reverse direction, as indicated by a minus sign. There is no other path it can take.
@@lecturesbywalterlewin.they9259 In a circuit you should define an edge orientation and then the current flows e.g. counter clockwise. To say the current flows from left to right on the downside and right to left on the upside is not so useful. If you have a ring current you would not work with infinity counts of directions and say the current of the upper ring flows in the opposite direction than the current in the lower ring... you would say the ring as an edge orientation and the current flows counter clockwise.
In part c) we have a closed circuit with a coil and two resistors R2 and R3 in series. If we define the edge orientation of this circuit counter clockwise, the edge orientation has the same orientation as the physical current I3 = I2 > 0.
sir i am student from india want to create website of lectures,homework and test of 8.01,8.02,8.03 in summer vacations if you agree i will create it for fun of programming
PEACE BE UPON YOU PRECIOUS GEM, BEFORE YOU GONNA LEAVE THE LIFE, MAKE SURE YOU BELIEVE THE TRUTH OF THE LIFE, AND REVERT INTO ISLAM, MAY ALLAH GUIDE YOU LEGEND
@@lecturesbywalterlewin.they9259 Well, Sorry if you felt it wrong, my intention was just to share it, DECISIONS R ALL YOURS....MAYBE U R RIGHT ON THE PATH YOU FOLLOW........ AND STILL I LOVE YOU MORE THAN BEFORE, U R THE LEGEND OF MILLION STUDENTS🖤🖤🖤🖤
thanks professor . We love you.
Whenever I watch @KeithandBridget solution, it inspires me to do even better with my solution 🙂,
Thankyou Keith
And
Thankyou professor for uploading this solution.
Thanks for the kind comment. 3 things I do that may help you. When I solve the problem I then put it aside and come back later and solve it again and check the two sets of answers agree. Second I watch the most relevant WL lecture I can find, 8.02 lecture 20 for this problem. Third I imagine explaining my answer to someone who has just watched the same lecture. Anyway I am glad I inspire you. This whole site is inspirational to me.
@@KeithandBridget Thank you,
Now, I will keep these three things in mind for my next solutions.
I really got awesome vibes with you i think i am in another world
Love u Walter Levin and physics
Hello Professor ❤❤
Thanks for an other UA-cam video professor 🌌☀️👏
I have great respect to u sir... Thank u so much 🥰🥰sir
thanks !!
Thanks Sir
I agree, good explanation. A bit british maybe :-) ...
Did you count my solution as correct or not ? I worked with the sub result and Keith expressed all current in R and V. Should I have done that ? Is it a requirement ?
I do not remember your solution. If you got the same 4 answeres as Keith, than your solution was correct
@@lecturesbywalterlewin.they9259I did not. I gave the formula for the parallel replacement value and used that in the answer as Rv. Is that wrong ?
@@lecturesbywalterlewin.they9259this iz normal))
@hanslepoeter5167
Yes. Your solution was correct.
@@ulfhaller6818Thanks for checking Ulf. Next time I'm gone write it out and simplify though.
You are the father of physics ❤
Hello Professor Lewin, I love your videos but attempting to understand physics causes me to think too much! BTW, who’s your haberdasher? ❤😊.
I bought this very colorful abd wonderful jacket in The Netherlands 2 years ago. It's only 1 of a kind and it was therefore not cheap.
You look veryvery good. I gave it up with Physics since Christmas. I hope, you will be my friend, as I'm yours, no matter what will seperate our lives. Could be, I will come back to Physics, because it is still my secret love.
Sir, I saw in a video that after rotating a rim wheel, you sat on a chair and the chair started rotating, but sir, in this situation all the force is internal and internal force never provides motion, then how did the chair start rotating?
no external torque, thus angular momentum is conserved. Since I changed the moment of inertia with my arms, omega changed .
Thank you sir for solving my doubt
Good morning sir, I have a question that in projectile motion, why only y- axis is taken for time of flight And why do not consider x axis for time of flight? I asked many teachers and professor but their answers are not satisfying.
you may choose any letter for any axis. It's a tradition to call the vertical y, but you may call it q or s or x or q
@@lecturesbywalterlewin.they9259 in my question y axis refer to y vertical axis with respect to x axis
:) tq
Professor I’m solving your electricity assignments . Please give me some advice about problem solving. I’m preparing for JEE. ( yogurt doesn’t work for me , kindly give me helpful practical advice)
you have 2 options
option 1: eat yogurt every day but *never on Fridays* That worked well for Einstein, also for me.
option 2: Watch all my 94 MIT course lectures. Start with 8.01, then 8.02, then 8.03. Do all the homework and take all my exams. *I guarantee you that you will then do very well on the Physics portion of any freshman college or JEE exam* You will find all information you need on this channel in three playlists "Homework, Exam, SolutionsY & Lecture Notes".
8.01 & 8.02 will each take about 200 hours, 8.03 about 250 hours.
@@lecturesbywalterlewin.they9259yogurt has also gone to America
Love from india ❤❤🇮🇳🇮🇳🇮🇳
Why Ampere's law fails in certain cases? When finding magnetic field at an axial point at the end of an infinitely long current carrying wire?
ampere's law never fails as long as you know how and when to apply it. You cannot apply it at the end of any wire regardless of its length.
A long current-carrying wire, with no closed loop, would be accumulating a charge at one end, and the opposite charge at the other end. If it is carrying a steady current, the charge would be growing at a constant rate. There'd still be a transient electric field immediately at the end of the current-carrying wire, due to the charge build-up. Ampere's law would still apply, you'd just be measuring a magnetic field of displacement current, instead of current.
Sir I'm in Class 8 and I want to know about the Fifth state of matter Bose-Einstein Condensates......please let me know......
don't be lazy, use google
@@lecturesbywalterlewin.they9259 okay sir
@@lecturesbywalterlewin.they9259😅
❤
😅
❤❤
❤
❤❤❤❤❤
Im sorry sir plz accpt it
What?
Think I see where you may be going with this professor, unless my imagination is playing tricks on me😉-🦅- Sorry about the high school physics - I didn't like the teacher and couldn't see the value in a lot of the work back then🤣 Will try harder when I have the time. Sabine Hossenfelder did a shorts video on the 5 most difficult physics problems if you want to have a look at it - I thought it was extremely helpful although could be wrong😅
Please professor give me how to study organic chemistry for class 11 please
Stop asking silly questions
I guess part c) is wrong. I1 = 0, I2 = I3 = (U - R1*I)/R3 with I := U / (R1 + R2*R3/(R2+R3)) (I = same current like I1 in part b or I3 is the same current as I3 in part b)
The energy is stored in the magnet field of the coil and the coil is then the battery, that means the current flows from one side of the coil through R3, then through R2 and then to the other side of the coil. So the direction of the current I2 must be the same direction of I3 and not I2 = -I3.
@@lecturesbywalterlewin.they9259 I understand what you mean. If you draw R2 on the same height as R3 right beside R3 the same current would flow through both resistors in the same direction (for the case c)).
In question c, I3 goes from right to left, but the current I2 goes from left to right. Thus they go in opposite directions
The current in I3 does not change direction when the switch is opened. So the current in I2 must reverse direction, as indicated by a minus sign. There is no other path it can take.
@@lecturesbywalterlewin.they9259 In a circuit you should define an edge orientation and then the current flows e.g. counter clockwise. To say the current flows from left to right on the downside and right to left on the upside is not so useful. If you have a ring current you would not work with infinity counts of directions and say the current of the upper ring flows in the opposite direction than the current in the lower ring... you would say the ring as an edge orientation and the current flows counter clockwise.
In part c) we have a closed circuit with a coil and two resistors R2 and R3 in series.
If we define the edge orientation of this circuit counter clockwise, the edge orientation has the same orientation as the physical current I3 = I2 > 0.
sir i am student from india want to create website of lectures,homework and test of 8.01,8.02,8.03 in summer vacations if you agree i will create it for fun of programming
*that would be a gross violation of my copy rights*
PEACE BE UPON YOU PRECIOUS GEM,
BEFORE YOU GONNA LEAVE THE LIFE, MAKE SURE YOU BELIEVE THE TRUTH OF THE LIFE, AND REVERT INTO ISLAM,
MAY ALLAH GUIDE YOU LEGEND
your truth is not my truth - however, I respect what you believe in
@@lecturesbywalterlewin.they9259 Well,
Sorry if you felt it wrong, my intention was just to share it,
DECISIONS R ALL YOURS....MAYBE U R RIGHT ON THE PATH YOU FOLLOW........
AND STILL I LOVE YOU MORE THAN BEFORE, U R THE LEGEND OF MILLION STUDENTS🖤🖤🖤🖤
@@NATION_EXPLODERdon't hurt the professor. He is already respected in the eyes of God. Because he is a useful person. Regards...