2-dimensional projectile motion part 5

[Kricardose]

I am very happy to see the vidoe The second part of the last projectile motion problem after you give this

[bebeheuy]

I Love The Video The second part of the last projectile motion problem It Can Increase My Knowledge

[Mjhond]

Steady I Really Like This Video The second part of the last projectile motion problem

[AyaSalvatore]

sal, do you know how awesome you are?? thanks a lot :)

[mrjcllc1]

Thumbs up for all of you that got to the last video of two dimensional projectile!!!

[feraligatr8]

My teacher told me that to get the horizontal velocity on a question like this, you should divide the total displacement by the total time. I thought that would give you the intial or average velocity though... Could someone explain why using the total distance and total time will give you the horizontal velocity? I have a shitty teacher....

[gigaguy101]

Are there practice problems on this topic on your website?

[Zwittz]

thanks now i can blow up my naughbor's house

[glitters171717]

what if the ball is thrown from above a building? how do u get the range and the time it reaches the ground?

[JackMoranRain]

d = v t, Wouldn't that be the average velocity and not the initial velocity.

[Seedofwinter]

@JackMoranRain it is average velocity.

[JackMoranRain]

@Seedofwinter But he says initial velocity. Is he making a mistake, or am i just getting something confused?

[Seedofwinter]

@JackMoranRain He is mis-speaking.

[OughtaBeFun]

@JackMoranRain Initial velocity is average velocity in that case. why? remember, we are looking at the ball travelling horizontally. There is no loss in velocity horizontally because there is no deceleration unlike the ball's vertical velocity which has deceleration due to gravity. With no loss in velocity, initial velocity is average velocity:)

[JackMoranRain]

@OughtaBeFun Wow, thanks so much for that, i acutely get now.

[Bella329]

i feel like the question doesnt make sense. Q: How far does the particle travel? ...he already told you. 100 meters.

[stephencrespo]

@Bella329

actually you'd be wrong. i think he was trying to solve for how far the ball would actually go in the air. if you were to extend the curved yellow dotted line to a straight line, its be longer than the 100 m

[animefreak619240]

Thank you, I will now raise my army.

[baeronautics]

nope THIS IS WRONG please read my coment to answer why.

he calculated vx of only horizontal component and vertical component right

so why did he take 100 as the dx ?because as horizontal component increases to 100 m then the vertical component would increase too forming a right triangle over the 100m line theta angle pointed towards to left i e, 30 deg. in short this problem is unsolvable u atleast need time or height to solve it feel free to reply because i want to prove i m wrong

[r3mixstyle]

i dont like how he teches this..

because hes making sin 30 to blabla bla..

it would bne much better if he just calclated everthing with sin x ..

its much easier 2 understand

[moesal2]

@r3mixstyle when ur at university level (3rd yr engineering) vectors you will not be allowed any calculators. So better get used to 30,60,90 and 45,45,90 triangles and their rules, so yea projectile problems will haunt you through out university.

[DartmouthAlum96]

Some people might try to solve this question using decimal values instead of square roots. If you are going the decimal route (i.e.--using Vx = 0.87Vi and Vy = 0.5Vi), be sure to set up your time as t = 2 (0.05Vi) or t = (0.1) (2Vi). Otherwise you'll end up kilometers off course.

[rubmasta1]

yuss, i now know how to command artillery

=)

[shinj1reyes6]

such a funny guy

[omgthatscrazyx]

Amazing stuff. math just works out

[jackncoke99]

Perfect. Exelent. 

[baeronautics]

@jackncoke99 nope this is wrong he calculated vx of only horizontal component and vertical component right

so why did he take 100 as the dx ?because as horizontal component increases to 100 m then the vertical component would increase too forming a right triangle over the 100m line theta angle pointed towards to left i e, 30 deg. in short this problem is unsolvable u atleast need time or height to solve it feel free to reply because i want to prove i m wrong

[kanguroman]

excellent video, and in here i can solve problems easily, but my stupid school is full of irregularities, and we get different professors that barely know the material they have to teach.

[MarvelsofaLifetime]

Damn these videos are just amazing. I never would've thought I would've learned so much. From what I knew at the frist video all the way to where I'm at now, is just a huge amount of information I've learned. Thank you Sal, again.

[Jaw6987]

That is awesomely cool lol

[UberCuba]

@Kev888

which exam board are you with

[alofuzion]

thank you!

[Kev888]

The exam board I'm doing A-Level physics with uses 'u' as the initial velocity and 'v' as the final velocity since 'u' comes before 'v'. We rarely use subscript.

[hellahulla]

@Kev888: I would hate to think I would fail my A-levels because I use V sub u or V sub 0 instead of u, or d instead of s or g instead of a.

That said I never took A-levels, went straight to college.

[danceathletics92]

thank u soo soo much ! u and these videos are amazingg ; truly helpful

thanx again :)

[iluvjiyongx3]

thanks again! i have to prepare for ap physics c for nxt yr, and ur vids are really helpful~^^

[bangalirussian]

ths shii is tooo easy...need sumshii more challangin....its da truth nothin rude....

[bangalirussian]

dude im an engineer...this phys bullcrap is da bread n butter of ma major...i had to master ths easy shii to earn ma degree....n btw i was a TA in phys in ma college....

[bangalirussian]

i was flippin through utube to checkout sum vids cause utube did help me wit sum calculus while i was a undergrad...n i happened to c ths vid which reminded me how easy ths phys is compare to my previous studies n decided to leave a note for sum stupid pplz...

[megaelliott]

I am 13 years of age and learning this for my pleasure so please stop calling people stupid. It is derogatory for you to call people stupid for learning from this video when you yourself were once at this stage. I am sure that one day this will be as intuitive to us as as it is alleged to be very intuitive and easy for you. Please think about what you have typed before posting a comment. Thank you.

[jagexownage]

lol, i'm the same age as you. Can you help me out with this stuff?

[megaelliott]

What do you need help with. Pm me

[cthugler]

no one cares! go ask your mom for a pat on the back.

these videos are very helpful :)

[gangstasal85]

i emailed him stuff on it but he hasnt replied yet i guess he is a bit busy, i asked him to do applied mechanics sort of questions you do in engineering

[azzyd12]

Easy for you maybe, but not all of us have masters degrees in physics.

Im doing AS physics and these videos are useful to me.

[ridiculousnoble]

ok this one lost me....too much trig, I tried using the cos 30 = .87 instead of the square root jargon and got a different answer, we never learn like this

[PianoWallaby]

Thanks for doing these. I have done something similar with brass instrument videos. Nice to see it done for physics and everything else you have done! Thanks again.

[w0247379]

Great, I just wish you didnt use radians, and explain your sub units.

[Nandine2]

wow

[canadiangurl523]

Good job!!! Love it!

[eldominicanboy]

nice