Dot vs. cross product | Physics | Khan Academy
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Understanding the differences between the dot and cross products. Created by Sal Khan.
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shout out to you for being a better teacher than... well.. my teachers
Best comment reward 👑
Its like when you have full interest on what teacher teaching and you listen to it carefully you understands everything clearly and thinks that teacher is the best creature ever👼
best comment reward 👑
Omg, sorry to hear that. I tbought this one sucked
@@mohammedadil7170no. Schools just pick the topic do it for a bit and move on to the next. To really understand it we need to do more selfstudy and practice stuff like questions. Schools doesn't have time to do all this and cover the entire syllabi, at least the way they go now. It's up to us. Also it's also depending on the teacher. Some teachers really have a way to make students understand thing by making sense out of things.
I was amazed with the drawing xD
Yeah me to
ikr!
Lmao
was looking for this comment haha
Dot Vs. Cross Product: Top 10 Anime Battles.
Literally Mannn.... 15 years ago!!!.. I was just 2 year old back than!.. Amazing.!!
ikrrr
I came here just for the awesome fingers
This video was released when I was born and still the best explanation video of this topic!
You are a mathematician as well as an artist. Well explained.
Thanks very much. Didn't get the dot product for so long, and in one video you gave it to me in such an nice and easy way to understand. Very helpfull. Wish I had you as a teacher in school ha
You sir are my hero. I wish my Calc teacher spoke with the same clarity and english composition as your video.
2:00 theta looks like ^_^
hahaha
ThX! sal
very funny, light hearted and informative. perfect!
one more thing ,can u please do a video on hydrocarbons-preparation of alkanes ,alkenes........etc.pleaseeeeeeeeeeeeeeeee
Thank you very much sir
Excellent! very intuitive. You have a clear way of explaining things. Thanks for the video.
good drawing for the hand ..m
That's good drawing right there damn
😆 Theta in 2:00 be like. 😆
:) I agree.
Khan is so cool! *draw a masterful rendering of hands, wait 30 seconds, ERASE!!*
around 7:00 it was a bit confusing cause in the sketch it seems like you are drawling a line perpendicular to b, not a (the little orthogonality square was hard to notice) and I said to myself "wait that is not possible, how didn't he notice THAT mistake?" heheh :)
Did not expect him to be such a goated artist out of nowhere wow
Is it only me who thinks soo or is Sal obsessed with the word intuition 😂
Thank you
I think I broke my finger. At least I can’t take the test now!
8:59 indian genes took over for a second there
what
Are you starting with an assumption that we are talking vectors? I thought dot product was like this: I walk a mile in an hour, how many miles can I walk in 3 hours? Scaler times a "thing" of some kind (dot product, a quantity). Cross product: basic electricity, V=IR. Suddenly two "things" are being multiplied together (current and resistence). Commonly, vector abstraction comes later. Isn't that the essential weirdness of reality, the cross product, emergence of a new "quality"?
Thank's❣❣❣❣❣❣
ur not only a good mathematician, but ur also a great artist! the hand!!
mashalla thanks allot brother.....
i have been learning art i can tell you that that hand is good, also you explained well, very well done.
I waited for my physics prof to say what the cross and dot products meant practically.
That was a mistake.
Dot product = a product of two vectors and a measure of how aligned they are.
Cross product = a product of two vectors, a measure of how crossed they are, expressed as a vector that is perpendicular to both of the original vectors.
He draws better hands on a computer than I do on paper. Gosh
This tutorial will only make sense to those who already know how it works.
Storytale He already made separate videos on both the dot and cross product so maybe watch them instead of criticising him for trying to help people
In my school the fee is so high but the way they teach is so unworthy for that money they teach 😭
anyone here in 2019?
me
thanks
thank you so much!! I managed to get an A1 in my exams just bcos of you :)
You are my God!
Aah 240p we meet again😀
Dot Product or the Inner Product between two vectors yields a scalar. Cross product x X y yields another vector....one orthogonal to the plane shared by x and y.
Nice fingers
you are good at explaining .
now its time to upgrade and explain through animation
easy way to remember (helped me)
dot is grayscale
cross is colored
Awesome youtube channel. Subbed and thanks.
perpendicular*
perpendicular*
2:01 SM--> SMILE :D nicee
Lovely hand drawing. fingers took the heart away ❤️❤️
'Hey Khanacademy! Sal here. Where are your fingers?'
The sin Theta is going crazy 😜... Had laugh alot in 12 years........
|a||b|sin() can be seen as the surface area of the parallelogram formed by the vectors "a" and "b".
Probably the worst video trying to explain a simple topic I´ve seen so far on youtube, especially if you compare it to 3blue1brown. Spending 5 minutes trying to draw a hand to then just say "yeah its like that" and another 5 minutes trying to talk about sinus/cosinus, what a waste of time.
if a (b)sin(angle) is the component of b perpendicular to a, then it should not necessarily be perpendicular to b. then Why do we say that it is perpendicular to both a and b
angel in cross product like 😀 this emoji 😀😊😊😀😀😀😀
do a tutorial for hand drawings lol :) :D
Thank you so much KhnAcademy. These are great sources!
Just found myself teo useful channels one khan academy and the other one's yours
Thank KA my professor doesn’t even teach you are a life savor 🙏
I am now watching a video that was posted two years after I was born, all because of my mathematics teacher 🙂💔
hey friends...plz tell me how r my videos
I could read the textbook for 2 hours or watch a khan academy video and skim the textbook
is that "perpindicular" misspelling?
2:40
HQ L
How do I find the sin of a smiley face?
Just ask Jesus for the sin list
any ib students ou there?
does it really matter?
I was reading this topic for more than one hour , but ur video gave me hope !
geometric algebra interpretation is much, much better. (a b) = (a . b) + (a ^ b) = |a||b|cos[theta] + i * |a||b|sin[theta] .... the cross product is a bad interpretation of wedge product.... (a ^ b) = i (a x b), where the cross-product obscures the fact that ordinary multiplication is related to complex exponentials.
hey champ, don't you have a whiteboard or a bamboo tablet with some shortcuts? you could boost your presentation style to "1st world"...
If i am watching a 15 year old lecture video at middle of a night, it means the value he provides is soo deep. Thank you ❤
Where the arbic language?!!
woa that arrow analogy for the cross product going into or out of the page is awesome. I wish i had had that when i was first being taught about current and magnetism and whatnotz.
he's not using a mouse. There are drawboards with a mouse pen.
YOU DIDNT ERASE IT YOU JUST COVERED IT UP ITS STILL THERE THATS SO DISTURBING
5:39
Shout out II-BS Math A PSU Lingayen Campus...😅
Thank you. It is really helpful for self studying.
I've got to stop looking at these videos, I really should be finishing my homework.
So is it collinear or not
Should have mentioned the relationship and reason why sine or cosine is used in dot or cross product.
wow, very helpful!
you mean orthogonal.
Simple and nice :) but the determinant way is better for understanding and tidy xD
why is axb not equal to bxa ? i didn't understand that part
It isn't equal in the sense that the resulting vector product will be in the opposite direction (180°), otherwise the value will be the same.
They are equal in magnitude but opposite in direction..... Anti cummulative
BAD HANDWRITING, BUT GOOD TEACHING
Sir the academy is khan so the teachers should be pathan😏
😂😂
At 2:02 the theta looks like a laughing smiley.
11 years ago !?
Very goo😂
veins? looks more like mickey mouse gloves
240p?
Thanks
thx and god bless you ^_^
Is the first letter always the index finger?
nice hd
A force = 4.85 Ni - 7.36 Nj acts at a location = 3.99 mi + 2.21 mj on an object. What is the torque that this force applies about an axis through the origin perpendicular to the xy-plane?
2
13 years in the future, love you
Five people don't want to learn anything.
lmao. I'm so confused
i wish u would be my home tutor who is a ocean of knowledge
What do ladders have to do with this?
great video! helped a lot!
The hand kind of looks like an old asian bunny.
OH that's the difference.