Physics 36 The Electric Field (5 of 18) The Electric Dipole

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  • Опубліковано 23 сер 2024
  • Visit ilectureonline.com for more math and science lectures!
    In this video I will find the electric field of the electric dipole.

КОМЕНТАРІ • 207

  • @aformula4198
    @aformula4198 3 роки тому +48

    6 years later and still helping students all over the world.thanks a bunch

  • @MohammadYaseen-oz6lo
    @MohammadYaseen-oz6lo 6 років тому +104

    I bet those dislikes are from grumpy physics teachers who dont want student's to pass LOLOLOLOL !

  • @allrated
    @allrated 8 років тому +17

    You are a life saver. I have been following you since last september and man, your explanation are spot on. Better than some of our teachers here in Montreal's polytechnique. Merci beaucoup!

  • @sergioakaliltroll20s
    @sergioakaliltroll20s 9 років тому +24

    have a physics exam for this tomorrow and you sir are an excellent teacher. great explanations and give pointers in areas where most educators would not bother to. thanks for your videos you are changing the world a student at time.

  • @thebilla6568
    @thebilla6568 9 років тому +82

    MY SYMMETRICALLY-HEARING EARS ARE HAPPY, FINALLY.

  • @VideoNinja117_Plays
    @VideoNinja117_Plays 9 років тому +3

    I have my physics exam tomorrow and this equation was never derived for me, thank you SO MUCH. I'm gonna look at the next ones too :D

  • @emersonmoss20
    @emersonmoss20 7 років тому +1

    THANK YOU SO MUCH for all your videos you've made for physics. Explaining the concepts behind everything has made University Physics so much easier for me.

  • @cadepeppin4581
    @cadepeppin4581 4 роки тому +6

    You have perfected the art of teaching.

  • @valeriereid2337
    @valeriereid2337 Рік тому +2

    I appreciate another excellent lecture. Taking E&M this summer, I must rely this channel to get me through it.

    • @MichelvanBiezen
      @MichelvanBiezen  Рік тому +1

      You are welcome. You will find all the topics covered in E&M explained in detail on this channel. 🙂

    • @valeriereid2337
      @valeriereid2337 Рік тому +1

      @@MichelvanBiezen Thank you!

  • @BINAYKUMAR-bs6ev
    @BINAYKUMAR-bs6ev 6 років тому +7

    sir..this was the exact same question i was looking for.. couldn't have got any better explanation...thank u very much sir..

  • @ashharkausar413
    @ashharkausar413 Місяць тому

    Absolutely brilliant. Straight to the point!

  • @gazmaska7593
    @gazmaska7593 10 років тому +2

    You are sent from the sky to save me! GREAT VIDEOS ! MUCH APPRECIATED
    BIG UP!!

  • @sruveerassathi
    @sruveerassathi 10 років тому +2

    Your videos are amazing! Please keep it going!! I would love to see more conceptual based videos as well (in addition to the numerical/computational based problems that you do).

  • @xXishibashiX
    @xXishibashiX 6 років тому +1

    You, sir, are a gentleman and a scholar

  • @chamerethomas3574
    @chamerethomas3574 3 роки тому +2

    great teaching! I finally understand how to do this problem.

  • @solsticetwo3476
    @solsticetwo3476 4 роки тому +1

    Nice lecture. It is relevant to stress, however, that a long distance (a>>d) the dipole behaves as a point charge with effective charge of q.d; and the decay of the electric field magnitude is to the power of minus three (instead of minus two), i.e, decay faster

  • @ritu932
    @ritu932 9 років тому +1

    The most simple and awsome explanation of this topin that i can get just cleared my doubts

  • @tasticxoxo7048
    @tasticxoxo7048 5 років тому +3

    Thanks for the lesson. It actually helped alot!!

  • @edricsantoso5341
    @edricsantoso5341 2 роки тому +1

    Best one out of all!! Thanks for the video Mr! You're truly a lifesaver.

  • @almostoogoodtobesue
    @almostoogoodtobesue 9 років тому

    This guy sounds like Christophe Waltz and I love it/him.
    Also--a clear, succinct explanation.

  • @NKShahariar
    @NKShahariar 6 років тому +1

    Thank you so much sir! It was so easy an explanation for so hard a topic (for me for the last 2 years)! You are an excellent teacher. Thank you again sir

  • @the_true_raikage6581
    @the_true_raikage6581 9 років тому

    Thank you so much, you are the reason I am passing physics!

  • @asaadalalawi3561
    @asaadalalawi3561 5 років тому +4

    i love your videos !!! Thank you!

  • @frenchfrythecool
    @frenchfrythecool 8 років тому +5

    Your videos help so much

  • @shadmanshakibalvi2897
    @shadmanshakibalvi2897 6 років тому +3

    Sir Your Lesson is just Amazing

  • @acecerio391
    @acecerio391 8 років тому

    Thank you so so much ... I was enlightened .. U answered my confusions ... Best teacher ever

  • @Knolittle-04
    @Knolittle-04 8 місяців тому +1

    the video of when i was 9 yrs still at primary grade 4 😂😂now using it at varsity😂...no need for a tutor 😂❤❤,,Merci beaucoup 👨‍🎓❤🙏

  • @mahas6952
    @mahas6952 6 років тому +1

    Thank you so much I have a mid term on this and this helped me so much

  • @_otunac
    @_otunac 9 років тому +1

    Great your videos, always perfect explanations. Thank you!

  • @rtha490
    @rtha490 8 років тому +1

    i literally pay hundreds to learn concepts that are explained in such a shit way. then there's this channel where i learn concepts just like that in a matter of 10 minutes. thanks bruh

  • @laiaplaiap1688
    @laiaplaiap1688 5 років тому +3

    Thank's doctor
    You're the best

  • @exposetechnology9907
    @exposetechnology9907 6 років тому +1

    please help,
    A water molecule has a permanent dipole moment of magnitude 6.2*10^-30 Cm. A water molecule located 10 nm from a Na+ ion in a saltwater solution. what force does the ion exert on the molecule?

  • @Borokıŋŋı
    @Borokıŋŋı 2 роки тому +1

    This video is lifesaver.. thank you so much

  • @odiraisaac7037
    @odiraisaac7037 2 роки тому +1

    Thanks once again..this what i requested last time 🙏🏼🙏🏼👍

  • @iksanmaulana1295
    @iksanmaulana1295 5 років тому

    oh my god,this the most very nice video how to explain physics on you tube..
    i'll tell to my friendsss
    love,
    Indonesia

  • @umeshpal3132
    @umeshpal3132 8 років тому +1

    so nice i understood very well thankzzzzzz

  • @hvsgtd
    @hvsgtd 5 років тому +2

    so helpful, thank you for your videos!

  • @AdabAbu
    @AdabAbu 6 років тому +1

    I'm thankful that I can help you through add revenue! thanks sir

  • @kipkoechezra6367
    @kipkoechezra6367 Рік тому +1

    Best ever,,, thanks Dr.

  • @muhammadsaimiqbal1551
    @muhammadsaimiqbal1551 3 роки тому +2

    will the Force be in the same direction as the electric field, and will we only have to multiply the formula derived for the electric field by q to find the force?

    • @MichelvanBiezen
      @MichelvanBiezen  3 роки тому +2

      The direction of the force on a positive test charge placed in an electric field is the same as the direction of the electric field.

    • @muhammadsaimiqbal1551
      @muhammadsaimiqbal1551 3 роки тому +1

      @@MichelvanBiezen thank you for your reply, Sir!

  • @toastygh0sty50
    @toastygh0sty50 3 роки тому

    Professor Van Biezen is the OG!!!

  • @hudayusuf4558
    @hudayusuf4558 8 років тому +2

    Thanks alot teacher u did helped me alot ☺

  • @patrickwalsh8299
    @patrickwalsh8299 8 років тому

    So is this true for ALL dipole? The y components will always cancel? PS Thanks for all the great videos. They got me through rotational kinematics and now E&M.

  • @rahultiwari9003
    @rahultiwari9003 8 років тому +1

    Sir what exactly is this electric dipole moment.Is it a force ???

    • @MichelvanBiezen
      @MichelvanBiezen  8 років тому

      +Rahul Tiwari
      An electric dipole is a particular arrangement of two opposite charges. When a positive charge is placed closed to a negative charge, the two charges close together like that is called an electric dipole. The electric field perpendicular to the line connecting the two charges has a particular equation as shown in the video.

    • @rahultiwari9003
      @rahultiwari9003 8 років тому

      +Michel van Biezen Sir but what is the significance of that word moment in electric dipole moment

  • @midnightsilverpuppy
    @midnightsilverpuppy 7 років тому +2

    Hey there. Awesome video. Your teaching style/method matches up with my learning style/method. Maybe you're just a good teacher, I don't know. But hey, I'm having trouble understanding around 5:30 why x^2+a^2 square root x^2+a^2 became (x^2+a^2)^(3/2). Maybe that's an algebra rule I didn't understand. Would you or someone care to clarify? Please and thanks yo

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +2

      The rule is: When the base is the same and you multiply you add the exponents. Example a^1 * a^(1/2) = a^(3/2)

    • @midnightsilverpuppy
      @midnightsilverpuppy 7 років тому

      Ok, thank you. Though, I'm still not seeing the addition equaling (3/2) 🤔. You have an exponent of (1/1) and you're adding it to the exponent of (1/2). I don't see what I'm missing

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +1

      1 + (1/2) = 3/2

    • @midnightsilverpuppy
      @midnightsilverpuppy 7 років тому

      Michel van Biezen haha, oh yes. Thank you.

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +2

      Isn't it strange how our brains sometimes just don't see something so obvious? (Happens to me as well).

  • @wishdoom
    @wishdoom 11 місяців тому +1

    you can do these equations very fast! thats impressive. for future reference i think it would be more effective for teaching first time learners if you went a bit slower

  • @AhmadRaza-gx1kv
    @AhmadRaza-gx1kv 2 роки тому +1

    thanks sir, you helped me a lot.

  • @mirishfaqahmad17
    @mirishfaqahmad17 9 років тому +4

    What is the value of electric field strength at the centre of dipole

    • @MichelvanBiezen
      @MichelvanBiezen  9 років тому +9

      Ishfaq,
      Take the final equation and set "a" equal to zero.

  • @ganeshk6574
    @ganeshk6574 7 років тому +1

    mr. van beizen why didnt you consider the negative sign for E2 ?

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +1

      We did by choosing the correct direction of the electric field caused by the second charge. Then we found the magnitude of the resulting electric field.

  • @yaqoobqp
    @yaqoobqp Рік тому +1

    Do you have any examples for electric dipole questions?

    • @MichelvanBiezen
      @MichelvanBiezen  Рік тому +1

      Just the one you are looking at. What specific examples are you thinking of, or is there a homework problem you are looking for?

  • @xvgx
    @xvgx 6 років тому +2

    How do i do this problem if the Qs are not equal in magnitude but different numbers and do not have the same sign? That would mean their corresponding
    vertical components would not cancel and would I have to calculate those vertical components as well?

    • @MichelvanBiezen
      @MichelvanBiezen  6 років тому +3

      Yes, you would have to calculate both components.

    • @egerazor
      @egerazor 6 років тому +1

      it wouldn't be a dipole

  • @sondossalah6904
    @sondossalah6904 7 років тому +1

    in the previous video,when we calculate the total magnitude of electric field ET, we say ET = square root of ETx^2 + ETy^2 ,but in this video we calculate the magnitude of ET as the sum of two x components .why we do that and what is the difference between two problems?

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +1

      That is what is so interesting about dipoles. The y-components of the electric field due to the 2 charges are equal in magnitude and opposite in direction and thus cancel out. The x-components however are equal in magnitude, BUT in the same direction, thus they are added.

    • @sondossalah6904
      @sondossalah6904 7 років тому

      okay but why we don't use the square root when we calculate the magnitude of ET ? ... when we can say that magnitude of ET = E1 + E2 ?

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +1

      Since the two x-components point in the same direction we can simply add them. Note that you only have to use the square root of the sum of the squares method if the components are perpendicular.

  • @MizzRiverP
    @MizzRiverP 9 років тому

    thank you so much! such a helpful clear explanation

  • @dalenassar9152
    @dalenassar9152 7 років тому +1

    Back in the day, master mathematicians called The "perpendicular bisector" of a line the "MEDIATOR". I wish I saw it more often...-hint-
    ps
    I think it originated in the field of geometry, then went general.
    Does anyone else know anything about this?

  • @hasangunes5574
    @hasangunes5574 7 років тому +1

    first of all thank you for videos. but i wonder something why dont you use 1/4piE0
    my teacher obsessed with it

  • @baselaljebali2274
    @baselaljebali2274 9 років тому

    what if one if the electric field on y-axis and the other one we should devaided it into y and x component, how to get the resultant of them?

  • @abdelz1617
    @abdelz1617 2 роки тому +1

    Thank you!

  • @milosalem3900
    @milosalem3900 4 роки тому +1

    What will the result be if the two charges are positive????

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому +1

      Then the components of the electric field in the horizontal direction will cancel and there would only be a component in the vertical direction.

  • @SYEDSHORABALI
    @SYEDSHORABALI 3 роки тому +1

    love you sir

  • @tsheporants3639
    @tsheporants3639 2 роки тому +2

    Thanks.

  • @soulseeker1651
    @soulseeker1651 10 років тому

    I'm curious sir, but at your final answer, the q, you say its the magnitude of the charge? Which charge, is it the magnitude of the two given charges?

    • @MichelvanBiezen
      @MichelvanBiezen  10 років тому

      soulseeker
      Either charge. (They both have the same magnitude, one is -q and the other is +q)
      Two charges with the same magnitude (but opposite sign) spaced closely together forms a "dipole"

  • @danieljoseph6404
    @danieljoseph6404 7 років тому +1

    why didnt you take -q as negative in when adding their cosines

    • @vikramram7011
      @vikramram7011 7 років тому

      Daniel Joseph he's already considered the negative sign while determining the direction it would act in

  • @victorhugodass
    @victorhugodass 10 років тому

    Very nice video.

  • @jalon85
    @jalon85 10 років тому

    Great video, very well explained :)

  • @terziwh
    @terziwh 8 років тому

    really good explanation. But what surprises me is that why do we ignore the sign of q. I am used to working in vectors so when i add them as vectors, not as magnitudes, I am supposed to get a 0 due to opposite charges. Could you explain this..

    • @MichelvanBiezen
      @MichelvanBiezen  8 років тому

      We don't actually ignore the direction component of the vector. In the beginning we draw the electric field component contributed by each charge. We labeled them E1 and E2. We then added them as vectors, and realized that only the vertical components cancel and that the horizontal components are additive. All we have to do then is add the magnitudes of the horizontal components to find the magnitude of the total electric field at that point. And the direction is in the positive x-axis.

  • @Monya97
    @Monya97 8 років тому

    You are amazingly great!! thank you so much

  • @annaxavier1775
    @annaxavier1775 8 років тому

    Usually axis is perpendicular to whatever we are considering. eg. in case of the earth (almost perpendicular to the equator). But in case of the axis of the electric dipole, why do we consider it along the dipole ?

    • @MichelvanBiezen
      @MichelvanBiezen  8 років тому

      +ANNA KAVALAM
      In more advanced courses we calculate the effect of the dipole from every direction. The simple case we only look at the dipole from a point perpendicular to the line connecting the two charges or along the line connecting the two charges.

    • @annaxavier1775
      @annaxavier1775 8 років тому

      +Michel van Biezen But Sir, my doubt is just about why the line connecting the two charges are named as axial ?

  • @sachinijayasinghe6177
    @sachinijayasinghe6177 9 років тому +1

    Gotta love that bow tho!

  • @teddyyu2415
    @teddyyu2415 8 років тому +1

    Beautiful.

  • @dimaali9786
    @dimaali9786 2 роки тому +1

    maybe i will not fail physics 102 after all.... thanks sir you are great

    • @MichelvanBiezen
      @MichelvanBiezen  2 роки тому +1

      If you watch the videos and learn how to do this problems (without watching) you will succeed!

  • @wyphonema4024
    @wyphonema4024 8 років тому +1

    I know cos θ = adj/hyp.But why is that hyp is x, not d?

    • @MichelvanBiezen
      @MichelvanBiezen  8 років тому +2

      +WeiFeng Ma
      The adjacent side is x and the hypotenuse is R in the sketch.

  • @Blake_47
    @Blake_47 6 місяців тому +2

    This explanation has some serious flaws:
    1.The angle for the negative charge isn't the same as that for the positive one as is clear from the diagram
    2.The electric field of the negative charge is considered negative but he chose it to be positive
    3.The distance towards the left of a should be negative

    • @MichelvanBiezen
      @MichelvanBiezen  5 місяців тому +1

      Nothing wrong with the diagram, the vectors, or the explanation. Not sure why you seem to think otherwise.

  • @syntaxerror2409
    @syntaxerror2409 3 роки тому +1

    can someone reply to me i need it ASAP, why did we disregard the direction and focus on the magnitude?

    • @MichelvanBiezen
      @MichelvanBiezen  3 роки тому +1

      Sorry, I didn't understand your question. ( I don't think we disregarded anything)

    • @syntaxerror2409
      @syntaxerror2409 3 роки тому +1

      @@MichelvanBiezen sorry for the confusion prof

  • @martin400
    @martin400 3 роки тому +1

    What if the charges r different

  • @ankushrana2001
    @ankushrana2001 4 роки тому +2

    Sir u r from which country?

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому +2

      I grew up in Belgium, but now I live in the US

  • @zulkifalaslam9420
    @zulkifalaslam9420 3 роки тому

    Point charges 𝑞1 = +12 nC and 𝑞2 = -12 nC are
    0.100 m apart. (Such pairs of point charges
    with equal magnitude and opposite sign are
    called electric dipoles.) Compute the electric
    field caused by 𝑞1, the field caused by 𝑞2 , and
    the total field (a) at point a; (b) at point b; and
    (c) at point c.
    Kidly solve sir

    • @MichelvanBiezen
      @MichelvanBiezen  3 роки тому +1

      Where are the positions a, b, and c?

    • @zulkifalaslam9420
      @zulkifalaslam9420 3 роки тому

      Positions a b c are not given
      But in diagram
      A is negative
      B is positive

    • @zulkifalaslam9420
      @zulkifalaslam9420 3 роки тому

      Sir can u give me your
      Email address
      Or
      WhatsApp number
      I will share problem screenshot

  • @erichgonzalez6685
    @erichgonzalez6685 5 років тому

    I wonder if I can simply find the angle using the inverse tangent. I've been doing that and my answer are always a bit off. I'm not sure if that's what I"m doing wrong.

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      Without seeing what you are doing it is not possible to respond to this question, but if you know the opposite side and you know the adjacent side and it is a right triangle then it should work.

    • @erichgonzalez6685
      @erichgonzalez6685 5 років тому

      @@MichelvanBiezen Thanks!!

  • @xx-mikanSwch
    @xx-mikanSwch 5 років тому +1

    Why do you express the equation in vector just put x head?

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      Since the vector only points in the x-direction we only need to show the x-component (using the x-unit vector)

  • @user-wv3fj5uu4h
    @user-wv3fj5uu4h 6 років тому +1

    thank you so much

  • @leonardkitti2950
    @leonardkitti2950 3 роки тому +1

    Thank you sir

  • @sayedshafei734
    @sayedshafei734 5 років тому

    Thank you ✊you're very excellent

  • @imeneyeddou6596
    @imeneyeddou6596 7 років тому +1

    excuse me but why we dont have to consider the negative charge in the expression of E2?

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому

      We did, so I am not sure about your question.

    • @imeneyeddou6596
      @imeneyeddou6596 7 років тому

      so in the expression of E we have to take the absolute value of q that's it?

    • @MichelvanBiezen
      @MichelvanBiezen  7 років тому +2

      Ah, you are asking about the sign of the charge? The sign of the charge only determines the DIRECTION of the electric field. The magnitude of the electric field only depends on the magnitude of the charge.

    • @imeneyeddou6596
      @imeneyeddou6596 7 років тому

      thanks a lot

  • @atekin99
    @atekin99 6 років тому +1

    thanks for this

  • @thounaojamanilsinghluwang1464
    @thounaojamanilsinghluwang1464 4 роки тому

    Sir I don’t find the lectures on dipole dipole interaction will you be uploading later or not please let me know sir your lectures are very helpful to us so kindly upload this topic too sir 🙏🙏🙏

  • @SadiqunhnabiChoudhury
    @SadiqunhnabiChoudhury 4 роки тому +1

    What would be the answer if both were positive charges

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому +1

      The the x-components of the vectors would cancel out the the y-components would add. Then it would no longer be a "dipole".

    • @SadiqunhnabiChoudhury
      @SadiqunhnabiChoudhury 4 роки тому +1

      @@MichelvanBiezen thank you.

  • @mebarkisouhila876
    @mebarkisouhila876 8 років тому

    une trés bonne explication,merci

  • @aimen4434
    @aimen4434 7 років тому +1

    What if both charges are negative??

  • @marwam3309
    @marwam3309 6 років тому

    Thank you

  • @dilanaktas6036
    @dilanaktas6036 4 роки тому

    Is it possible to obtain the zero electric field for this system? Do you have any idea? Please, help me

    • @MichelvanBiezen
      @MichelvanBiezen  4 роки тому

      Since the 2 charges have the same magnitude, there is no point anywhere where the electric field = zero

    • @dilanaktas6036
      @dilanaktas6036 4 роки тому

      @@MichelvanBiezen thank you so much

  • @saikatazad5631
    @saikatazad5631 9 років тому

    thanks, it was helpful.

  • @MsVicki1997
    @MsVicki1997 8 років тому

    How would we determine the field if it was at some point P, instead of on a bisector. How do we solve this if we cannot exploit symmetry?

    • @MichelvanBiezen
      @MichelvanBiezen  8 років тому

      With a dipole you typically pick the point along the perpendicular bisector. But if you want to fine the electric field at any other point, the vertical components would not cancel out and you would have perform an integration twice, once for each direction.

    • @MsVicki1997
      @MsVicki1997 8 років тому

      Ok... i tried it earlier and ended up with a trig sub! And a two part equation!

    • @MichelvanBiezen
      @MichelvanBiezen  8 років тому

      Yes, that is a difficult problem. I should do an example or two like that. (I'll put it on the list of videos to do).

    • @MsVicki1997
      @MsVicki1997 8 років тому

      Awesome! Thank you so muuch!!

  • @fobpower60
    @fobpower60 10 років тому

    THANK YOU!

  • @fouadhaidar3640
    @fouadhaidar3640 8 років тому

    Thank you, sir

  • @garretthall6342
    @garretthall6342 10 років тому

    I like the new bow tie :)

  • @TheGamingg33k
    @TheGamingg33k 7 років тому

    Thank you my man

  • @yavuzozulu5694
    @yavuzozulu5694 6 років тому +1

    ÇOK İYİ Bİ HESAP TEŞEKKÜRLER

  • @thesarcasticjerk2328
    @thesarcasticjerk2328 5 років тому

    sir where can i find the video for electric field expression for a electrical dipole for axial position and any random position other than axial or vertical . please help . i need those urgently .

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому

      I don't believe we have such an example.

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      That said, it is worked out exactly the same except that the y-component doesn't cancel out and you'll have to calculate both the x and y component of the electric field.

    • @thesarcasticjerk2328
      @thesarcasticjerk2328 5 років тому +1

      @@MichelvanBiezen sir its easier said than done for students like me ... it would have been of great help if u could have put another video explaining that ... anyways thanks a lot for your existing videos ... they help a lot

    • @MichelvanBiezen
      @MichelvanBiezen  5 років тому +1

      Yes, we realize that. We are still working on adding more videos as time permits.

  • @master16789
    @master16789 9 років тому

    Odd flashing of black marks on the whiteboard from 4:30 to end of video....

  • @lostboy9586
    @lostboy9586 6 років тому +1

    Cool man

  • @zachang3428
    @zachang3428 6 років тому +1

    lifesaver