Kinematics Part 3: Projectile Motion

Things don't always move in one dimension, they can also move in two dimensions. And three as well, but slow down buster! Let's do two dimensions first. You know, like a cannonball. This is called projectile motion, and it's super important in physics. Isn't this getting fun?
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1000dollars and cant spell college

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@@txu6666 last time i checked i was engineering student not english 🤔

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Azar Last time I checked, academic writing is a big part of college, idiot.

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[@gauravtripathi7918]

Pls repeat kinametics chapter one more time maybe you miss projectile motion.

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Had an hour lecture on it and left with nothing lmfaoo

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college? I gotta learn this for grade 11 😭

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It's unfair this is our lesson in grade 9

[@elevent33n79]

😭the assignment that decides whether i graduate or not

[@kennethringo9137]

Heads up: If you input -14^2 / 2 x -9.8 you will get 960.4. This is because the equation itself is ambiguous. You will need to input -14^2 / (2 x -9.8) and it will give you 10. This is for the checking comprehension part.

[@renzorvillecaidoy1308]

hello My apologies , still professor Dave's equation in the last part is ambiguous .

[@renzorvillecaidoy1308]

hello its negative 10 , why is its positive 10 ?

[@renzorvillecaidoy1308]

why we need to divide where infact there is no division part in the formula

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Agree

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Hamze k that was my same reaction except without the n word lol

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Thank you so much Dave! This video helped me fully understand something I couldn’t wrap my head around over the course of a 2 week unit.

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My teacher was unable to teach me this concept with 3 classes with each 50 minutes but this video did in just 7 minutes. Thank you so much really grateful.

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Your explanation for independent x and y motions is spectacular! Thank you!

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You made this concept incredibly simple. I was struggling with applying it because I was completely overthinking it. This video clears things up. Thank you so much! 😀

[@DavisbestonBeston-gz3zw]

Very true😃

[@truemusic3064]

In the given problem, D=−100 meters represents the vertical displacement of the object, which is negative because the object is falling downward from a height of 100 meters above the ground.

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Ok I’m 1 Minute in and I can alr see me failing my physics test tmr

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How'd it go

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thats exactly whybi failed physics 2 times, i kept telling myself im gonna fail, once u retake physics or actually comprehend physics ur gonna be like “i was doubting myself for no reason its not even that bad” 100%

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@@jamaljones4714 well I can now confirm that I did fail that test but I just buckled down and actually studied for the nest one and that counted for half my grade and I did surprisingly well so it’s Alr

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In 2023 It tooked me 5min to understand "2 weeks of school explanation" just because ur making it easier by giving simple examples from real life UR A GENIUS

[@marigussio8723]

Professor Dave , you helped with the Projectile Motion unit for physics. I really did not know how to solve this question for physics but you helped with that so thank you.

[@ce-cesworld4382]

hi professor dave I have a question. you said to use -100 for the displacement. Do you always use -100? Thank you!

[@ProfessorDaveExplains]

No, that's the height of the cliff.

[@ce-cesworld4382]

@@ProfessorDaveExplains ok got it thank you!

[@HowdyElSalvador]

Thanks, I had the same question! 🤦🏽‍♀️

[@HorizonSpeed26]

got the answer for check comprehension first try ,YES!

[@Alice-wy7ih]

Can I ask you a question? hahaha I don't know why is my answer is -5.6 how did you get it?

[@nigelgeorge43]

There are three types of projectile motion: 1) Vertical Projection (no Horizontal motion) 2) Horizontal Projection off a cliff/ledge (No vertical motion initially but develops throughout the trajectory due to gravity) 3) Angular Projection (in this video) Just thought I needed to highlight these.

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thank you so much for this!!! couldn't understand my teacher for the past two weeks, yet you helped me understand the entirety of parabolic motion in just a couple of minutes.

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Wow you are the best, I literally learned this with one video when I couldn’t during class. And it even has a comprehension check!

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Make sure calculator is in degree mode for the trig functions

[@lbtheman12345]

Is there anyway to solve for time without the quadratic formula. For example, change in Velocity (y-direction) = (acceleration due to gravity) * (time)

[@sethtulud7802]

how did you solve for the time? I tried it using quadratic formula but I got 19.288

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this has helped me sooo much, i went on a vacation during the start of my physics course and my teacher gave me no help. This has taught me more than my teacher could in 2 hours

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The reason this guy's method of teaching is so effective is because he teaches things in such a way that a student would understand, too many teachers like to overcomplicate the concept instead of breaking down the fundamentals.

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This video is really well done, thanks Professor Dave!

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“We have been throwing alot of rocks lately and lets throw another one from our favorite 100 m cliff”😂😂😂 this made me laugh so hard !!! Love your humour and appreciate your work alot sir❤️❤️❤️

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[@angelkhatetuano3467]

why did the time become 4.97 seconds???? can someone explain that to me!!!

[@maianna2768]

MY EXACT QUESTION RN AHHH

[@JenniferRokks]

he used the quadratic equation formula and got two different answers but time cant be negative so the time answer is the positive one.

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it is the best of all video lectures it really helps me to understand my report

[@dennisdesalme]

This video really broke it down well. Thank you so much. I really like that you used the original kinematic equations, rather than canceling and deriving a new equation for max height, which I don't want to memorize.

[@imyasharya]

Oh thank you, I understand it at last after 1 months. I didn't knew how these vectors split works but now I know it and in a better lovely way...

[@dharanijena6423]

Thank you very much sir.

[@xavierbahunsua7871]

i honestly didnt get how you got the -4.10 and the 4.97 answer sir, i do not know about the quadratic equation. help

[@ProfessorDaveExplains]

check out my mathematics series! all the help in algebra you will ever need.

[@RocketFriday]

x = A + B + C 0 = -4.9 + 4.25 + 100 Using the Quadratic Formula: x = - B + | - √B^2 - 4 * A * C ------------------------------------ 2 * A Dunno why "Professor Dave Explains" cared more about viewership than sharing that knowledge but that's what you're missing.

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Thank u so much. My professor made it so difficult. I have been trying to solve these exercises for hours and your video just helped me out in a few minutes. You are an angel.

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PROFESSOR DAVE EXPLAINS is the best KZbin channel.. I don't watch any other

[@mojahedkhaled480]

WHY IS THE ACCELERATION -9.8

[@jianyanchoong5762]

Mojahed Khaled acceleration due to gravitational force

[@quisharamos902]

why i cant understand it tho i watched it many times :((

[@aarohanyt7374]

Basically if u throw something at the sky , it will travel in a parbola like shape 2 motion takes place 1)vertical motion 2) horizontal motion Lets say u throw at 30degree from a horizontal(imaginary) with initial velocity of 2 m/s Now come something intersting into play , we know you are throwing the rock at an angle at the sky (like a diagonal) So lets break that single vector into 2 vectors Vx along X axis (along ground) ,Vy along Y axis (a straight line drawn towards the sky which is perpendicular to ground) Visualize this situation ! What happens ? The rock goes up to certain height and falls down (that height is called maximum height ) The staring point and ending point of rock is on the ground and this length is called the range Interesting thing here Vx represents horizontal motion Vy represents vertical motion When we spilt a vector into 2 perpendicular vectors ,its called resolution of vectors ( look this up on yt to clear things up) So what we do is , the vector u (intial velocity with we throw the rock) is spiltted into ucos30 ( along the X direction ) and usin30 ( along Y direction ) we take ucos(theta) as horizontal motion because (theta) is the angle made by our inital vector with the horizontal(the imaginary line which is parallel to the ground ) The horizontal motion of rock(ucos(theta)) remains constant in projectile motion because there is no disturbance or force The verticle motion goes on increasing , reaches maximum height and goes on decreasing . Thats it just focus on vertical motion which changes due to g When t=1s , Vy =usin(theta) -g*1 When t=2s , Vy =usin(theta) -g*2 Whent t = n s , Vy =usin(theta) -g*n

[@rubyhaas5986]

Hey Dave, could you explain why you used this specific kinematic equation at the end of the comprehension question? I used the delta x=v(i)t + 0.5 at2 equation and got a different result.. Thank you very much!

[@ProfessorDaveExplains]

can't use that one, we don't have any information regarding time!

[@JungGung]

i have a question professor.....do angle of trajectory,,,affects the applied force? example if you want to reach vertical distance....do you need a lot force if its90degrees and lesser if its30degrees?

[@mrabdullah7078]

@@JungGung it is kinematics . We don't study force here

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Real

[@peterhayman]

so helpful splitting into x and y, i didnt get it until watching your previous two videos, thanks!

[@dillon8518]

Why do I get d=40

[@dmytrolatysh9244]

-196/(-19.6)=10 You multiply 1/2 to (-9.8) thats why you got 40.

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You saved me from failing a test. Thank you...

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after watching this video i finally got some level of comprehension of what to do with these type of problems. Thank you good sir!

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in 7 minutes it has explained 3 hours of teaching in a better way thankyou, saved me for a test i have in an hour

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Thanx for making concepts clear

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my brain stops working sometimes....I hear him speaking but can't make sense of what he's saying uuughhh

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Bro take a nap lol it helps

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that's ur fault

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He's trying to give so much information in shortcut that's very common on KZbin..you just have to replay the video 2 or 3 times that better than watching a 21 min video xD

[@junesept234]

Play it in slower speed.

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Try to drink coffee. It improves focus

[@greatbaracuda6164]

hi . in the movie gladiator or the likes, warriors shielded themselves in a phalanx formation as waves of arrows raining over them that are coming from wall battlements from long distance: Does the arrows have enough energy or velocity to penetrate the shields (or even just the tip embed the surface) when fired in a parabolic path at long distance VS shot from straight line of sight at short distance? edit: answers in layman appreciated. no maths and physics please 😁

[@madeleinecallan3153]

In order to not have to do the quadratic equation, you could know that vox = vo(costheta initial)t and voy=vo(sintheta initial ) -1/2gt^2 For objects that are simply released not shot or thrown with a vo other than zero, you can infer that no angle is made.

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i feel stupid :(

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People here are from college? Im a 3rd year highschool student😂

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I understood it, but it was kinda like looking at an incomplete picture. Still cloudy in some places. Really helped put it together thanks a lot

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Iam a 8th class student but you made me to understand more than 10th standard ! Thank you sir 🙏

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Thank you! My teacher just started using trig and was like “ok that’s how you do it” without any explanation!

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THANK YOU!! you are a blessing to my college experience

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Thank you so much professor dave, you made this a lot easier to understand. I was watching other videos that weren't very comprehensive on this topic and you did a great job!

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Sir..You are really genius..We are lucky to watch your channels.... Thanks for sharing your excellent knowledge..

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This thing fucks me up…i’m a Grade 12 doing grade 11 physics..

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HE IS GENIUS!!!

[@colem.8914]

went through 2 weeks of this stuff in physics not understanding 2d projectile motion at all, but this cleared it up so much

[@santhikadimisetty2950]

to find the time taken,why do you take the velocity for Y axis

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I'm surprised that students needed to learn this in order to become a coffee maker. 🤣

[@mustafanaik5866]

wow thats crazy! thats also MY favorite 100m cliff.

[@ashms5980]

Thank you so much for your help!

[@TheBoyWithABike]

6:20 I have a doubt. Isn't cos 30 = (3^(1/2)/2) Then V along Y axis should be 28 cos 30 = 14(3^(1/2)). Then h max = 30m if I'm right. Pls answer this doubt

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I joined the family and told other physics deffulters to join and subscribe

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