I'm watching this in 2021, this entire series has been a game changer for me in competitive exams... I dont know if you'll read this but Thank you OP for all the patience.
This videos 8 years old and still helped me so so much. Especially now , when we have online classes, I barely understand what the teachers saying. But this helped me understand 3 to 4 classes' worth of syllabus. Thank you so so much sir !!!
I like how you planned out your lesson visually before giving it. I also like how you break things down and go back a few steps to clarify. Thanks, this helped a lot.
Instead of talking about sin and cos (which scares many and the vector opperators can be introduced BEFORE trig) If we just say B is a unit vector then A.B is the length of the A vector in the direction of B and A x B is the length of A cross wise for the direction of B I think that is easier
It's true that it's probably easier, but sin and cos are not that scary, and if you're going to learn electrodynamics, you need to get comfortable with them. There are several places in EM where it doesn't make much sense to think "in the direction of" or "in the direction perpendicular to". It makes much more sense to just bite the bullet and think of sin and cos and waves.
@@Tiffany-wb4ln I'm going to keep this one up and link to the new one via a card. Here's the new one: ua-cam.com/video/rL2RnbZp5TM/v-deo.html Join me on Discord: discord.gg/TGK47Pf
I think it is easier to first introduce the dot and cross product in 2 dimensions then you can just say the cross product also produces a number Ax By - Ay Bx Later when you do it in 3 dimensions you can tell them the cross product is actually a vector strait out of the page.
+jg394 sir i have a doubt , I understand that in cross product we have a sin theta in the formula , but when we have two parallel vectors we can have a vector which is perpendicular to both .. but why does the cross product of two parallel vectors gives us nothing even though we can a vector which is perpendicular to both,
Cool stuff, but one small thing. It's not pi degrees, it's pi radians, and they're two different things. Pi degrees is 3.14 degrees, pi radians is 180 degrees. Different measurements.
That's just the way it is. It's a definition, and from the definition flows all the properties. Think of it this way: We have these things in math that are done that way. It turns out that there are many things that do things in a similar way. So mathematicians said, "Let's give this method a name" and hence, the dot and cross products. Now, instead of describing the process each time we need to do it, we just say "dot product" or "cross product" and everyone understands what it means.
I already did. Yes, you can do the component-wise dot or cross product, but I find that it's only useful for solving problems and does not help you understand what they are and how they actually work.
My actual question is how does the cross product of 2 vectors give vector and dot product of two vectors give scalar????i want justification plz...can i get my answer...
There's different notation systems. In Physics, we use a, b to represent magnitudes. The vectors are either in bold (in textbooks) or with an arrow. The basis vectors have a caret on their head, which we call "hat".
You'll have to memorize which product you need. If you can't remember, the dot product yields a scalar, while the vector product gives a vector perpendicular to the factors. 99% of the time in physics it's the dot product you need, except for rotational kinematics and magnetics.
+Vipin Swami I am not sure which entrance exams you are taking or what they ask. I don't know that I can help except to say that you can practice solving problems that might appear on the test. Understanding each part of the problem and its solution is the key to understanding how to solve future problems. Don't let any details escape your study.
+Vipin Swami It sounds like you are freaking out during the test. This is how I would calm myself down before a test: - Study well in advance - The day before the test, stop studying, take a mini-vacation, get lots and lots of sleep - During the test, I would tell myself that I studied as hard as I could, and I can do no better. I would remind myself that I am human just like the people around me taking the test. The only way I could do better is if I were more confident and relaxed so that I can release my mind to do its thing.
Thanks for putting all this content together! Only, you should get a white board and an eraser. I think you are using way too much paper! But great job, and thanks again!!
Why oh why is a dot product scalar and cross product is vector... that is my only issue... I get all of it but why is dot scalar and why does it use cos ? Why is cross product a vector and why does it use sin ?
This is a really old video, but it is by far my most popular. I'm rebooting my channel, so please subscribe and check out my newer videos. Thanks!
Old is gold :)
Nice video Sir
I, uh, are you a hippie? I, uh, don't know how to say this and be polite at the same time, but uh. Never mind. 🙃
I'm watching this in 2021, this entire series has been a game changer for me in competitive exams... I dont know if you'll read this but Thank you OP for all the patience.
My prof had a 3 hr lecture on this topic and I still didnt get it. Now, I'm here for almost 9 minutes and i learned everything. Thanks, old but gold.
I am watching this video on 16 September in 2019. It is very old but still very helpful 🙏❤️❤️🙏. Love from India
I wish people would watch my newer videos. I am embarrassed with how poorly this was done.
@@jg394 no sir this made me understand and aced my test and got like 85%
helped me a lot
This videos 8 years old and still helped me so so much. Especially now , when we have online classes, I barely understand what the teachers saying. But this helped me understand 3 to 4 classes' worth of syllabus. Thank you so so much sir !!!
Wow!
I don't think I've ever heard that comparison before and it makes so much sense!
This is what i was searching for 1 month
This was like 20th on search results and yet was better than the top 19 combined. Thanks so much, man!
I like how you planned out your lesson visually before giving it. I also like how you break things down and go back a few steps to clarify. Thanks, this helped a lot.
Hurray !!! My doubts are cleared... Thanks a lot !!!!
Exam on monday,, LETS DO THIS! ahaha
Great job dude , 8 min worth it to watch . Not waste of time at least in your provided video
+Navid Rasouli Thanks!
Probably the best explanation about this I've ever seen or read.
*perpendicular
Kelvin Malitao 90* angle
Kelvin Malitao
*😂
Instead of talking about sin and cos (which scares many and the vector opperators
can be introduced BEFORE trig)
If we just say B is a unit vector then A.B is the length of the A vector in the direction of B
and A x B is the length of A cross wise for the direction of B
I think that is easier
It's true that it's probably easier, but sin and cos are not that scary, and if you're going to learn electrodynamics, you need to get comfortable with them. There are several places in EM where it doesn't make much sense to think "in the direction of" or "in the direction perpendicular to". It makes much more sense to just bite the bullet and think of sin and cos and waves.
By convenience right hand rule is use to denote the direction of the resulting vector from cross product.
Had right hand rule explained so many times, never understood it till now. thx
Bro ,this video helped me out to answer the fastest in my class..... Thank you bro.
Cross product is an area of a parallelogram.
How to know if we’re supposed to use dot product or cross product?
my god, this helped me so much to understand what the scalar product was. thanks so much!
I want to redo this in the near future.
@@Tiffany-wb4ln I think this week will be THE WEEK. I'm worried as this one video has been responsible for 1/3 of my ad revenue from UA-cam.
@@Tiffany-wb4ln I'm going to keep this one up and link to the new one via a card. Here's the new one: ua-cam.com/video/rL2RnbZp5TM/v-deo.html
Join me on Discord: discord.gg/TGK47Pf
Thank you for devoting some of your time to educate us!
WHAT A GREAT COMPARISON! THANK YOU! YOU'RE A GENIUS! YOU SHOULD BE A TEACHER !!!
I think it is easier to first introduce the dot and cross product in 2 dimensions
then you can just say the cross product also produces a number Ax By - Ay Bx
Later when you do it in 3 dimensions you can tell them the cross product is
actually a vector strait out of the page.
We don't got time for that, unfortunately. It may make sense mathematically but nothing in EM will make sense in 2 dimensions.
best explanation ever
👍
+jg394 sir i have a doubt , I understand that in cross product we have a sin theta in the formula , but when we have two parallel vectors we can have a vector which is perpendicular to both .. but why does the cross product of two parallel vectors gives us nothing even though we can a vector which is perpendicular to both,
There are an infinite number of vectors perpendicular to two parallel vectors.
Cool stuff, but one small thing. It's not pi degrees, it's pi radians, and they're two different things. Pi degrees is 3.14 degrees, pi radians is 180 degrees. Different measurements.
+Roald Amundsen Very good point.
Ronald A going to find this comment!
thank you🙏🙏
thanks for explanation but it would be better if you show in detail by drawing them and what really means to multiply vectors.
Yes thanks
Is there any new video on this?? This is fab and lovely.❤❤😘😘
That's just the way it is. It's a definition, and from the definition flows all the properties.
Think of it this way: We have these things in math that are done that way. It turns out that there are many things that do things in a similar way. So mathematicians said, "Let's give this method a name" and hence, the dot and cross products. Now, instead of describing the process each time we need to do it, we just say "dot product" or "cross product" and everyone understands what it means.
Very helpful. Thank you for making this tutorial. I hope you will make more videos and I am looking forward to them. I just subscribed.
Please show how to do product in cross and dot
I already did. Yes, you can do the component-wise dot or cross product, but I find that it's only useful for solving problems and does not help you understand what they are and how they actually work.
Thanks for helping me you saved me ❤
i like it, you guys kill, now i understand them better
2:42 - 2:51....0, π/2, π RADIANS not degrees, that would have confused the fuck out of me if I saw it a year ago.
Correct!
+Josh Javaherian Sorry, after a while you just stop using degrees and always use radians. Degrees and calculus do not mix.
Can you explain why we can't have a cross product of 4d vectors
How many of ya'll up at 2 am tryna understand
Good Presentations! God bless you! Keep the good work!
Thank you very much!! Wish I had a teacher like you
Sir you did your best l like your way of teaching thanks
thanks for it :) I'm sure I will never confuse :D
Dear sir i have a one question plz u tell me why we use cos with dot product and sin with cross product
great lecture
+ihonestytruthful Thanks
Thanks man really cleared up a lot of things
the best! thank you saved my life :)
Clear teaching
Thq sir
Nice writing
best explanation😊
U cleared my doubt thanks
Thank you very much from Ukrainian student in Poland.
My actual question is how does the cross product of 2 vectors give vector and dot product of two vectors give scalar????i want justification plz...can i get my answer...
Thank you
Thanks for the answer
Nice comparison!
How is a vector cross a vector equal to 0??
When they're parallel or antiparallel.
Nice break down! It clicks very well ... Thanks for your time and effort!
Nice it really helps sir! :)
why in dot product there is cosine but not in cross product and vice versa explain please....
should write as |a| |b| as they are magnitudes right
There's different notation systems. In Physics, we use a, b to represent magnitudes. The vectors are either in bold (in textbooks) or with an arrow. The basis vectors have a caret on their head, which we call "hat".
big thanks helped a lot in my studies ty ty ty ty ty!!!!😊😊👏👍👌👏
"squezee" 7:54 , Great lecture btw thanks ^_^
Great job! Thanks.
Correct explanations dude
very good video ...
What does n^ represent in ab sin teta n^ ??
The unit vector in the direction of n.
Thanks for letting me know 😊
Mohammed Khalandar n^ represents unit vector,which is perpendicular,to a×b vector
Radians but not degrees.22/7,180
7:55- 8:00 okk forget it😅😅
this is realy wonderful and amazing.
I'm from India.
Nice video
Hello India! I get a lot of viewers from India. I guess you guys care about math and physics over there.
Only during exams😂😂
thank you, sir!
*Perpendicular
Is dot product same as inner product ?
Yes, but we use "dot product" more often in Physics. "Inner product" suggests linear algebra, which is nice but not what we are thinking of.
jg394 I was learning for a linear algebra exam i wanted to make sure it's the same.
Why in the dot product it is Cosine theta (maximized when parallel) while in the cross product it's Sine (maximized when perpendicular) ?
Thanks
sanmukha great experience
if in any question we have to find product then how we 'll know that there we use scalar or cross products
You'll have to memorize which product you need. If you can't remember, the dot product yields a scalar, while the vector product gives a vector perpendicular to the factors. 99% of the time in physics it's the dot product you need, except for rotational kinematics and magnetics.
+Real Physics where we use dot product nd where we use cross product
If we have ab sine theta where theta is 90 degrees then surely the two vectors are perpendicular ? It's rather confusing
sine of 0 is 0. Sine of 90 degrees is 1. Sine is maximized at 1 when the two vectors are perpendicular, and minimized at 0 when they are parallel.
@@jonathangardner4842 Yes but it is saying the resultant is at 90 degrees to the plane in which the two vectors are already in.
Can somebody please give a real world example when to use each? These formulas mean nothing if I don't know why they are used.
thank you so much you clear my doubt in few minutes!!!!
+Vipin Swami No prob. I'll likely remake this video since it is so popular.
sir tell me how to improve my physics ? i am not able to solve questions during entrance exams
+Vipin Swami I am not sure which entrance exams you are taking or what they ask. I don't know that I can help except to say that you can practice solving problems that might appear on the test. Understanding each part of the problem and its solution is the key to understanding how to solve future problems. Don't let any details escape your study.
I am taking medical entrance exam for MBBS. I practice alot but my mind did not work during exam for physics but same questions i can solve at home
+Vipin Swami It sounds like you are freaking out during the test.
This is how I would calm myself down before a test:
- Study well in advance
- The day before the test, stop studying, take a mini-vacation, get lots and lots of sleep
- During the test, I would tell myself that I studied as hard as I could, and I can do no better. I would remind myself that I am human just like the people around me taking the test. The only way I could do better is if I were more confident and relaxed so that I can release my mind to do its thing.
Perfect!! thanks!!
Good job dude!!
Thnx !!
:)
Thank
Sukriya.
thank you
Thanks for putting all this content together! Only, you should get a white board and an eraser. I think you are using way too much paper!
But great job, and thanks again!!
Thank you🥲
Why oh why is a dot product scalar and cross product is vector... that is my only issue... I get all of it but why is dot scalar and why does it use cos ? Why is cross product a vector and why does it use sin ?
Ho my god 8 years old but the concept is stil young now it 2020 sep....😄love from india.
Nyc love from india
Did you check out the newer video, with 87% fewer errors and mistakes?
Dang white out!
What is a*b equals?
it helped me so much.....thanks😅😅
Thanku sir I have my exam tomorrow love from india
where's your son? thought he'd be joining you again and soon start his own channel to show off what he's learned :D
real explanation
I love it😍
Nice
I laughed so hard when he was saying "this is not gonna work is it" at 7:50 nd that squeeze XD lmao
Sir. What does n hat means
"n hat" is the basis vector in the n direction. It has unit length, a length of 1.
It means unit vector
Mamta Mitawa n^ represents unit vector
Very helpful. Thanks so much!