The bizarre thing is that they chose to "drop" phi from the Z axis down as opposed to making it the intuitive "up" from the "equator" (or in terms of elevation for telescopes, gunlaying, etc). I wonder why this was the case (apart from avoiding negative values).
Phi is the angle that is made from z- axis to the line of projection of point P. This angle goes from positive z axis to overlying x-y plane then to negative z axis and completes 180 degrees in its pathway.
Yeah I get that, but she says that (3sqrt2, 7pi/4, -7) ((roe, theta, phi)) is also an acceptable answer and I disagree because like you both said arctan range is restricted from -pi/2 to pi/2. Theta should also be in between these values. 7pi/4 is greater than pi/2.
Shouldn't phi be changing along the x-y plane while theta changing vertically? I think you accidentally interchanged phi and theta in your illustration there. Unless, it is just a matter of convention?
I'm not sure whether my question applies here, but... Suppose you have a point (lat, lng) on a sphere of radius r, and you also have a point (lat2, lng2) directly "north" of the first point at a distance d. How do you rotate the second point on the sphere, clockwise about the first point, while keeping its distance constant?
Imagine r and theta (from 0 to 360) as rings. So for each phi we get a corresponding ring on the xyz plane. So now a sphere is made of rings from top to bottom right? ( i.e. phi from 0-180) If u take phi from 0-360 you are counting rings twice. (top to bottom and again bottom to top)
My calc professor showed me the other day. think of a coin. Lay it flat on the xy-plane. Rotate the coin vertically. You'll see that you only need to rotate that coin half way for it to "create" a spherical shape. you've only rotated that coin 180 degrees which is why you can consider the range from 0 to pi and you could calculate for the entire sphere. Hope that helps
Feels great knowing why equations work instead of just memorizing them. Now during a test I can reason out equations. Makes me really enjoy math.
+Cihan Barnett RIGHT, they teach it wrong in school
PWskates this is my teacher 😂 she’s having us watch her video for class
@@andrewrafaelkim You are lucky :D
That’s the gist of learning math
One, less, you enjoy meth!? Like, what did just happen at the start of maths message!
Edit: massagein
you're a LEGEND, keep up the amazing work.
This is great explanation, thank you for putting this up
That was incredible thank you so much
Man..... Such an incredible teaching !!! Probalby you love what you're doing, aren't you ;) ?
Thanks, and I do love teaching math.
Great video!
GREAT explanation. THANK YOU!
Thank-you.
Awesome explanation! Thank you!
such a nice explanation..
Thank you:)
Beautifully explained. Thanks
Thank You!!!!!
The bizarre thing is that they chose to "drop" phi from the Z axis down as opposed to making it the intuitive "up" from the "equator" (or in terms of elevation for telescopes, gunlaying, etc). I wonder why this was the case (apart from avoiding negative values).
Phi is the angle that is made from z- axis to the line of projection of point P.
This angle goes from positive z axis to overlying x-y plane then to negative z axis and completes 180 degrees in its pathway.
Mind adding times where you actually start talking about spherical coordinates?
Thanks a lot. Very well explained.
Thanks ...Nice work...Truly nice work
that helped a lot thanks!
really helpful! Thank you very much!!!
hey whats the value of cos45* please check the video
root 2 over 2
again thanks for the hieroglyphics of cal 3
Isn’t arctan restricted from -pi/2 to pi/2? 9:14
Yeah I get that, but she says that (3sqrt2, 7pi/4, -7) ((roe, theta, phi)) is also an acceptable answer and I disagree because like you both said arctan range is restricted from -pi/2 to pi/2. Theta should also be in between these values. 7pi/4 is greater than pi/2.
*did not specify range at first, but I meant to say range is restricted*
@@akeirsteadmath So is -pi/4 not the correct representation because theta is from to 0 to 2pi?
@@akeirsteadmath Why not 3pi/4?
@@akeirsteadmath actually I see why it would not be 3pi/4 because that not be pointing at (3,-3) 4th quadrant in xy
your teaching skill is great kudos to that but would've preferred a few tougher numericals.
Shouldn't phi be changing along the x-y plane while theta changing vertically? I think you accidentally interchanged phi and theta in your illustration there. Unless, it is just a matter of convention?
Sorry. It seems like my reference, Elements of Engineering Electromagnetics by N.N.Rao, uses a different convention.
Janiz Suyko You think it wouldn't be too much to ask to have consistency within math rules...but no dice....
Lack of conventions is a pain in the arse
I'm not sure whether my question applies here, but...
Suppose you have a point (lat, lng) on a sphere of radius r, and you also have a point (lat2, lng2) directly "north" of the first point at a distance d. How do you rotate the second point on the sphere, clockwise about the first point, while keeping its distance constant?
That's what you do from the center between them.
thanks very easy to remember........
What is the reason physics guys use theta from z axis and make problems worsen
Pretty helpful!
Helpfull preetttttttyy!?
@@ramseshendriks2445 Yes, very helpful back at that time!
What if your phi angle is a negative?
thanks ,very helpful.
Thanks for the excellent video. Just a typo in x-y plane instead of (3 x Squre root of 2)
can anybody explain me that how phai is varying from 0 to 180 degree in spherical co ordinate system..????
Imagine r and theta (from 0 to 360) as rings. So for each phi we get a corresponding ring on the xyz plane. So now a sphere is made of rings from top to bottom right? ( i.e. phi from 0-180) If u take phi from 0-360 you are counting rings twice. (top to bottom and again bottom to top)
My calc professor showed me the other day. think of a coin. Lay it flat on the xy-plane. Rotate the coin vertically. You'll see that you only need to rotate that coin half way for it to "create" a spherical shape. you've only rotated that coin 180 degrees which is why you can consider the range from 0 to pi and you could calculate for the entire sphere. Hope that helps
For some reason my uni uses the theta for different coordinate angles in spherical and cylindrical, but still very helpful video
can someone tell me how we consider the range of values for theta?
... in rads
I thought in cylindrical, it's rho,phi and z
Possible translate to language Arabic now I follow you please
ty!!
Thx!
tnx from nice teaching !
9:30 should be 3pi/4
that might get changed
more hieroglyphics
omg..i almost thought it was Hillary Clinton speaking 😂
tashW nice vape videos 😂
Dina Key
love you anne
She sounds like Sarah sanders 😂🤣😂🤣😂🤣😂
But her explanation is awesome
Great but it would be better if you start pronouncing phi as FAI