Horizontally launched projectile | Two-dimensional motion | Physics | Khan Academy

[@delwlr]

I'm watching this the day before my physics exam lol

[@cappuccino2901]

how did u got?

[@keane6635]

lmao fuckin same HAHHAHAHHAAH

[@herrerarafael1914]

Im watching this just minutes before final exam

[@maharajdattumaharaj5360]

I'm watching on the day of exam, I have 2 hrs left for the exam

[@codyclark7525]

right there with you lol

[@ericaritchie9136]

I am such a visual learner and I do online school so it's hard for me to teach myself some things especially in physics. This really helped me, i appreciate it.

[@oneagainsthumanity7893]

3 years later and all we have is online school

[@josephpate7646]

@@oneagainsthumanity7893 this person is probably in college now😪

[@oneagainsthumanity7893]

@@josephpate7646 Damn i never thought about that 🤭😔

[@fumikotsukumi017]

“They REAAAAALLLY want to plug in 5m/s as the velocity in y; but don’t do it, it’s a trap.” I like this dude already

[@premseelan]

"People are just *dying* to stick that 5m/s in there..." 😂

[@xx-gamer-xx9476]

i swear i understood everything thing more than the class

[@andreasbringemeier3689]

why arnt my physics teachers this good?

[@charliephinney9105]

Looks like your English teachers aren't the best either.

[@chiraggupta2645]

Lol....same

[@carlenger9707]

Your profile picture makes you look like you're 5. There's literally no way you're in physics.

[@MsOluyemi]

Svensk Gamer that could be his son -.-

[@nadineebada6557]

@@MsOluyemi or his brother

[@stormwolf4488]

Hopefully the cliff diver doesn't ignore air resistance lol

[@xanthman7528]

If they do ignore it, then that's pretty impressive.

[@MathPhysicsEngineering]

To those are intrested in an in-depth analysis of the physics and the gometry of teh projectile motion, with simulation and visualization I recommend: kzbin.info/www/bejne/foHImXaLq5uVe7s&ab_channel=Math%2CPhysics%2CEngineering

[@mimichfury6329]

U clearly understand students soo damn well mate. My mind is oficially blown by your teaching.. thnk yu mate

[@MegaJefflin]

This teacher is better than my teacher, finally someone explain this with human language, and also this teacher is fun, dont try this at home lol

[@rubycannon]

Thanks! My physics teacher bores me to sleep and I end up learning some of it on my own time. Wonderful explanation!

[@jorgezheng5169]

Words cannot express how much you have helped me. My gratitude for you is endless.

[@migueldiax7947]

I am in AP physics this year and the teacher blew through the first few “recap” lessons, I didn’t take any prior physics class so I’m in a loop lol. Very well explained!

[@jacobtlg9029]

This guy litterally saved my grade. I am a freshman in highschool. Im not very smart but the school still decide to put me in physics. I am so lost all the time. It also doesnt help that my teacher is kind of bad at teaching. I think she might have dementia. REgardless thank you so much for this awesome video you really helped with understanding horizantally launched projectiles.

[@kaylynn3459]

Lmao I love this! I’m in the library without headphones, and this so amusing with no sound and the captions on because of the humor. Thanks for the help!

[@Unveiiled]

Really helped me, got my a in the exam! :)

[@temi7036]

Thank you so much!! I have a physics test tomorrow on horizontal projectile motion and you explained this really well

[@dawitergichofanta7093]

The most open person ever. YOU ARE THE BEST, DAVID

[@davidsscope]

I searched "why greater heights provide further distance when jumping into water" because of the movie "Deep Water Horizon" showing Mark Walberg climbing higher up the drilling platform before jumping to clear the fire in the water. Now I know why he did what he did. And your teaching skills are amazing

[@jaydenandrews8847]

How do you do this if you’re given the range but not the y value

[@Furzayra02]

Thanks this was very helpful

[@Landoscurlyhair]

Thank you so much for this! 😭 my school doesn't do lectures but instead just give us notes. This topic, they didn't really elaborate about this one and tomorrow is our exam, FINAL EXAM. 😭. Now I understand everything about this now 😭

[@shanks6190]

I'm watching this DURING my physics exam

[@boshtua]

Got a test tomorrow and I have no idea what I'm doing, I'ma watch this and hope it helps

[@liquidmo5543]

Ah yes, no one jump off a cliff at home

[@thecurryoflife3]

11:17 How come the time t wasn't squared?

[@altunartuch5094]

Because half of zero is just zero times by t squared is just zero the last part if the equation doesn’t matter

[@waffielz3106]

a video not made by khan? praise the sun

[@jean-christopheboucher6306]

you save my night! thanks a lot!

[@bishaldas6790]

More efficient than my phy classes

[@justinkim4861]

taking the class next year wish me luck!

[@codedballs]

Justin Kim good luck

[@waffielz3106]

try hard

[@lixinz.4708]

5:25 how is gravity -9.8 if your object is going down and the gravity is constantly facing downward? wouldn't it be positive?

[@nidhiupadhyay416]

No, acceleration is a vector quantity and object is falling downward.

[@jacobpickos733]

I love this. Thank you.

[@jikunue9187]

you should be my physics professor!

[@tobiiyarou]

i genuinely wanna meet this guy

[@m4lmas]

5:25 best teacher ever

[@malanil1]

lol

[@cmackatlanta]

How would we determine the angle at which the person hits ground at various distances?

[@amarlist1]

the sound effects are great, i like Sal, cuz hes prob like super smart af, but this narrator is great too, 1:45

[@muneebanjum6268]

BEST EXPLANATION EVER!!!

[@kyandrew7942]

learning this 1 hour before our examinations

[@stephanieshen3713]

God bless khan academy

[@allanerissat2296]

Like Bucky Roberts, but in Khan Academy! Great video!

[@MegaJefflin]

lol, exactly, but this one is funner

[@phendyella9742]

I finally get it . Thank you

[@ModjadjiMamaila-cs4ek]

U are really a good tutor

[@glob567]

thank you so much, this really helped me finally understand this

[@saraowens8413]

Great video. This just helped so much! I was having such a hard time with this. Thank you!

[@chard0nka]

Hey thank you for this video & explanation! Really helped me in reviewing for my physics quiz!

[@toereh7848]

I’ve learned more from this than 4 months with my teacher

[@ntokozosikhosana-zj5nr]

What we solving for how far, are we solving vertically or horizontally?

[@alstugvideos]

This might sound strange but what software are you using?

[@iron1349]

This stuff makes a TON more sense when you have a calculator to help with finding square roots

[@mixedguy2038]

I love the way you teach

[@Yourlocaljp]

BASED DAVID!!! Thank you

[@voyager7971]

Thanks for the refresh!

[@jacobgordon6052]

Any idea what program they use

[@brianbruno1786]

Can you do colliding??

[@celebrityfan6870]

At 5:38 you said acceleration downwards is negative. How is that possible it is working along with gravity so it has to be positive right? Someone pls explain

[@heavens.sorrow]

I believe it's just written as a negative because acceleration requires a direction so, the negative symbol is just a placeholder per say for down for Voy.

[@xox102]

How do you find the height of the cliff given the velocity and the the distance it landed?

[@alanjacob1488]

Basically use eqns of motion and apply proper sign convention. For other cases too, when projected at an gle theta above and below horizontal

[@connorb7182]

10:28 I recommend keeping it as Δx because for the students who have already taken calculus may get dx confused with the notation to integrate. Edit: I'm only 13 and I'm watching this lol. I'm learning physics and biochem because there really is nothing else to do I took pre-calc in 4th grade.

[@breazfreind402]

"Edit: I'm only 13 and I'm watching this lol. I'm learning physics and biochem because there really is nothing else to do I took pre-calc in 4th grade." here's a famous quote that i personally made, im also rlly smart i think smarter, see: "I don't care about your start, i care about your end". I heard all these "geniuses", "prodigies" but they become really nothing at the end. I hate the use of "genius" in such a familiar and ordinary word applying to everyone. make something unique and then i will regard, for now i see you as ordinary

[@breazfreind402]

forgot to mention, you are cringy , self-respecting, idiot, has no friends, thinks his smart but brain says no and so much more and u have the audacity to say words like that make my blood go red

[@SlowKlone]

yeah no they won't, there's not even an integration sign. Also, that edit is really cringy dude, nobody cares that you're smarter than other people.

[@breazfreind402]

to emphasise, your pretentious edit is more larger than your post. shopping list "your mom as a account name" "maximilianus avatar ". 3 months ago you had a different avatar stop being so trendy trapoline

[@mufidhmuhsin2314]

I am 13 too. Well I do calc too. Shits ain't a big deal

[@xwllxi]

Bro, I watch your videos the day before the exam.

[@ziyadfara4760]

What a beautiful video. Explained so well. Great teacher.

[@alstugvideos]

Thank you very much for this.

[@wenymwila5021]

Physics I see you Thank for the video sir

[@zaneninjago410]

this is great thanks!

[@TheScienceCube]

Even If 20% of the teachers in the world start teaching like this, the world will advance a lot faster!!

[@rakiedi8347]

Such a good Explanation 👍👏 It helped tnx 😊

[@tusharahmed3151]

aweosome man. very good explanation

[@BMitts]

This literally is more helpful than the videos my teacher makes

[@babarm9815]

This has to be the best video ever.

[@peppervfx]

My teacher accent is kinda hard to understand so helps out a lot. Thank you.

[@uzmajamil105]

Thank youu

[@The_Unintelligent_Speculator]

Yes. I could have been a genius with this sort of tuition. Cheers 🍻

[@keniatorres5598]

can anyone explain how to do the math portion once he gets to the radical

[@adilmohammed6897]

hi, so when you take vertical displacement (dy) as + 30 instead of -30, you will find that the value inside the root (that long line, i am assuming that's not what they call in your country) becomes negative. now, the square root of negative numbers come under the family of complex numbers and most calculators aren't build to do that (cos complex numbers are imaginary and unlikely anyone is gonna use irl) hope it helps

[@maki4568]

A bullet is fired 30deg to the horizontal with a speed of 200m/s. The acceleration of the bullet is 15 m/s^2 vertically downward What is the change in velocity after 2 seconds?

[@lopamudrakar5680]

Hey! Initial velocity= 200 m/s, final velocity after 2s= 186.81m/s, the change in velocity after 2s is -13.19 m/s.

[@lt.ifeplumz1315]

Velocity only changes during vertical motion. So, we are neglecting the horizontal motion since the velocity here is always constant. During vertical motion, Acceleration =Δv/t. Initially, during the vertical motion, the initial velocity is usually zero. 15ms-² = Vf - 0./2s. Vf = 15ms-² × 2s. Vf = 30ms-¹. ΔV = 30 - 0 = 30ms-¹.

[@successparody]

I found this extremely helpful. I really appreciate what you guys do. Thank you

[@bla__berries]

Lol. This part of projectile motion always confused me but I love the way it was explained here. I even laughed😂. I do not laugh while learning physics.

[@elialanaable]

what if we needed to find the total distance?

[@EllietheEngene]

is there a vertical version of this?

[@Physics841]

perfect explanation

[@gurkaransingh1922]

great video ,i understood everything ☺

[@giovannadealca3187]

thanks for it😁

[@jhelseaamarixe4475]

do we only give a e -9.8 going upwards if it is in free fall?

[@shrekkosswampinar7088]

Thank you. This video helped me a lot

[@klydeurbiztondo3601]

Regarding the value of downward acceleration due to gravity, why did it happen that it is negative? When in fact the object/body is accelerating not decelerating? Can someone explain?

[@carultch]

The sign on acceleration has nothing to do with whether the object is speeding up or slowing down. A negative sign on any kinematics quantity just means that it is opposite the direction you arbitrarily define as positive. It is customary to define up as positive, but you don't necessarily need to do this.

[@rennibae]

Watching this before my Physics Midterm next weeek 😓

[@rheanng1920]

thank u !! my physics textbook nor teacher does this good of a job lol

[@jologendary]

can i ask why you multiplied both sides by 2 on the equation of getting the time?

[@LinhNguyen-ff3on]

Thank you this was very helpful!!

[@Hino_55]

Key takeaway is: The elapsed time for the motion of the object represented in its x & y component motion is the same for both x & y components. Well explained Sir David! Thankyou!!!

[@trinitywirth9329]

My saving grace

[@markkaranja11]

What if we are asked about the horizontal and verticle components of the velocity when the object hits the water?

[@annc6152]

thank you I love you.

[@Sam-rg7tg]

Thank you so much it helped a lot

[@snapebtwalt]

THIS WAS SUCH A GREAT VIDEO DAVID > SAL

[@starboii568]

Why is the acceleration negative if you are going downwards

[@isonif2503]

thank you very well explained

[@lopamudrakar5680]

Good!! Anyways, in 1:26, that is the case of a suicide!!🤣🤣🤣

[@aSuspect1]

Thankyou so much

[@byehikaveh]

Thank you so much! Im not going to fail my physics test tom

[@sanskaragrawal8167]

David speaks like Kenny Sebestian 😂😂

[@KirtiSanghani]

From which country and in which grade ? I am curious to know

[@carlenger9707]

8:38 "It's a trap"