Physics Lesson: Vector Components Part 2 for high school

[KarlaAllure]

how did you get this Ax= -5.1 m and Ay= -6.1?

How do you know that? :O

[Gutsyndicate]

physics is stupid, there are so much pitfalls and unnecessary obstacles just to solve one problem.

sign could be negative or positive depending on the direction, the angle could be plus or minus 180 depending on the quadrant, the acceleration could be negative or positive. equations could be different depending on the horizontal or vertical component, on top of that there is a drawing or diagram, and unit conversions and dimensional analysis also at the end, just for one stupid question.

[PhysicsEH]

@Gutsyndicate True but when you get it you understand how the universe works. Be proud of what you've learned because so few ever try to understand physics.

[Bakugantsuvai1]

What if my teacher gives me a crazy question and the triangle is not a right angle?

[TheInuLogical]

I'm in physics honors and my teacher goes waaay too fast. This helped a looot!

[PhysicsEH]

@TheInuLogical I'm glad to hear that they helped. Good luck with your course.

[mozahemi]

I lost you when you wrote Ay= 8 cos 40! isn't Ay cuz of y you should write Ay= 8 sin 40?

thats what you guys did in the previews video 0.o?

[PhysicsEH]

@mozahemi Hi. Ay is not always "sin", sometimes you use "cos". What you need to know is that once you draw the triangle and the angle, you need to figure out if Ay is the opposite side or the adjacent side of the triangle. If it is the adjacent side, use cos, if opposite side, use sin. The decision to use sin or cos depends on whether Ay is the opposite or adjacent. In this video Ay is adjacent so you write Ay=8cos 40. I hope this helps.

[XsoEmiXD]

I'm in grade 7 , and I'm tring to reach physica this high! And I don't quite get it.... Mostly the part where you find the 8 cos 40 degrees. which equals 6.1 according to this video ?

[PhysicsEH]

@XsoEmiXD If you even understand a little of this you are doing very well. Keep it up.

[XsoEmiXD]

@PhysicsEH Thanks, and I actually do understand a little of it. I am in advanced math, and wanna keep it that way... :)

[BlueFire666]

Massive Beard envy. 

[PhysicsEH]

@BlueFire666 Thanks. I'll let him know. You should see it in the winter.

[justforthelulzzz]

i am in grade 9 and looking at becoming a theoretical physicist. I was wondering if you could tell me were i could start looking at what i will learn in highschool and a good place to start and to understand the more complex formulas.. thanks

[PhysicsEH]

@justforthelulzzz Great question. Our website (shown in the info box of the video) is a good start. In most places physics is taught over 2 senior years in highschool with some taught in the junior grades. On the website it indicates which videos are mostly for the introductory course, grade 11 and the second year grade 12. The topics we cover are probably common to most schools so if you watch them you will see what most high school physics courses cover. I hope this helps.

[justforthelulzzz]

@PhysicsEH I will take a look and i will be taking grade 11 physics next year, my highschool offers a thing that you can take classes during the summer to get a spare but I am going to use it to do grade 10 science so I can take grade 11 physic's because i find it very interesting. The good thing about this to is that I can in grade 11 take grade 12 physics so then in grade 12 i can have a spare to do work or take another science class, thanks again i will check it out

[PhysicsEH]

@justforthelulzzz Great plan. I would suggest you do it.

[LordIllidan98]

The oppsite side is always the side where the smallest angle is facing? What if both angles where 45? Which one would be opposite and which side would be the adjacent?

[luirot9]

Wow now I remember why I liked mechanics once back in junior year of H.S. These folks make it seem so simple. On the other hand elec and mag is disgusting!!! yuck!

[FaisalLover]

why are we taking angle 40 in the formula.. if we have given 540 ... plz help..

[PhysicsEH]

@FaisalLover

Hi. I think what happended is that it looks like we wrote at the top of the board 540 degrees in the square brackets. It is supposed to be [South 54 degrees West]

The "S" for South looks like a "5"

Sorry for the confusion. If this does not clear it up, please let me know.

Thanks.

[vicosal1]

@PhysicsEH

I am having trouble with vectors as an element of structural design where X and Y are flipped and resultant equals direction.for example why is everything done from counterclockwise from positive X -when (-) should start at (-) Y...........example:R=4.123@ 284 degrees Counter Clockwise from X axis would be drawn

[zaishaloveu]

@FaisalLover i more way u can say that its not 540 is that..thr can never be 540 angle...u can not have more then 360 bcz thats a circle!!

[rascalturi]

I have seen in Part 1 that along x- axis we take cos theta and along y axis we take sin theta. But i saw that in this partnyou took sin theta for x axis and cos theta for y axis.. Is it due to that x and y axis are negative here. PLz reply.

[PhysicsEH]

The vector is the hypotenuse and you have an Ax and Ay component. For the component opposite the vector, its the vector x SinΦ (let Φ represent the angle)

for the component adjacent to the vector, its the vector X CosΦ

In the Part 1, Ax was the adjacent side to the vector so it is the vector X CosΦ

In Part 2, Ax was the opposite side to the vector so its the vector X SinΦ.

It does not matter if it is the x or y component, it's whether it's the opposite or adjacent side of the triangle.

[ellamissa]

can the adjacent side be on the negative x-axis (i forgot what that's called in trigonometry) and the opposite be going down from that?

[PhysicsEH]

Yes. You can go along the x-axis to the left first then down, or (as we did) along the y-axis down first and then to the left. Both give you the same components.

[rexman92]

@ellamissa best part of this is that theres no worries about any tall basketball players blocking the fiew thus leading to failure of note taking thus most notes would not be there thus leading to ither a fail or a low grade

LOL

[rexman92]

@ellamissa oops wrong persion ment the vid owner to comment on

[cargonuts]

Does anyone know how to solve for a plane flying due north - say going 420 kms per hour, for two hours and finds himself 120 kms northeast of his expected destination? I'm used to problems with a given degree, so the due north part really screws me up- to find the magnitude....

[TheZeroBeats]

omg it just improved me in physics im far further than the rest of my class xD i study this in my spare time i just love science and physics and astronomical stuff though its kinda hard because i live in europe i learn every thing in english :D

[TheZeroBeats]

Ps : guys what does the M stands for Metre ? or magnitude or what .. in the place where i live its metres but that means that the Vector is 8m (8metre) ?

[amirshirafkan]

@TheZeroBeats small "m" is metre. large "M" is errr........we dont use "M" in physics

[TheZeroBeats]

@amirshirafkan ye i figured that out in like mmm 6 months ago but thx i guess...

[AWICKEDPRODUCTION]

THANK YOU! well explained

[sammywilloe]

Hey, great video. It helped a lot! Please make more.

[PhysicsEH]

Thanks. We love to hear that they help. Our plan is to make some more.