Physics Lesson: Acceleration Down Ramps w/Friction Part 1 for high school

[Michael5029]

i wish someone would hit the button...

[bibbabby]

@Michael5029 lol



[cirrusxfeiri]

thank you!!:D

[wishingstars163]

My physics teacher spent like weeks trying to teach these concepts to our class, but he drones on forever and no one ever understands him! But this! This is AMAZING!

Thank you so much for your help! :)

Keep up the awesome work!

[PhysicsEH]

@wishingstars163 Thanks for taking the time to let us know you liked our videos.

[klegendk18]

this man can draw extremely straight lines lol... great videos keep it up

[stuffnotyou]

You make it so easy. My teacher spent a week trying to teach us this and I still didn't get it. 4:56 minutes with you teaching and I finally get it. 

[NewYork026]

Thank you oh so very much!!! Dont stop your preachings keep goin :)

[Rby202]

why is that angle 30 degrees?

[klegendk18]

@Rby202 only because he chose that angle, it could have been anything he wanted to choose

[klegendk18]

@Rby202 using basic Z patterns and other angle methods you are able to find the angle b/w Fg and FgY

[crewsd]

this is SO helpful, thank you!

[AnotherBrownKid]

thanks!

[coexistordontexist]

this is so helpful just as a recap before i do my homework. now, instead of bs-ing numbers the period before, i /want/ to do my physics homework and i /can/ participate in class... because now i understand what i'm doing. i can't thank you enough

[XianRaodon]

wonderful wonderful wonderful aid this is!

[peter1234930]

soo helpful, my physics teacher has been piling work on and i had no idea what was going on until now

[kariinbebz]

Thank you so much!! Your amazing video has un-confused physics for me :)

[shawol159]

How did you get the force of friction to be 15N or is it part of the question?

[SiikP90]

I love how you guys do care. I mean you made this vid like two years ago and you're still replying to these comments. Thanks.

[Melvel22]

This is a really big help. Thank you for taking your time to do this. I think i speak for everyone when I say I appreciate this.

[soromon9]

Yes! That help

[PhysicsEH]

@soromon9 Glad we could help.

[PhysicsEH]

@ptsampras14 Hi. I don't think I can explain it without a diagram. you need to make the bottom horizontal line of the ramp long enough to hit the Fg vector. This creates a triangle with the horizontal of the ram, the ramp and the Fg. this triangle can be used to prove that it is the same angles as the triangle using Fg, the ramp and the bottom horizontal of the ramp. Unfortunately I can't explain how you use this to calculate it. Sorry.

[Freekymooga]

I hope you realize how much your helping students like me. Thanks for taking the time out of your daily lives to make these videos. I wish my teacher was as clear and concise as you guys. :)

[PhysicsEH]

@Freekymooga Thanks for your kind words. Glad we could help and best of luck with your course

[804YankeeFan]

Wow, youre one of the best teachers i've ever seen. I really love physics so I really enjy your videos! keep the great work up !

[PhysicsEH]

@804YankeeFan Thanks for the really great comment.

[dhaccessories]

You are the BEST teacher in the world!!!

[PhysicsEH]

@dhaccessories Thanks for the great comment. Glad we could help.

[NOCOMMENT3176]

I don't know why, but the sound of chalk on blackboard just sounds so...nice xD

[PhysicsEH]

@NOCOMMENT3176 Then you must love school.

[VloggerTan20]

I heard there was a way to go up a ramp, could you help me on determining this?

There was a double sided cone that went upwards from a triangular ramp.

[PhysicsEH]

@VloggerTan20 Hi. I'm not sure exactly how to answer the question you are asking. There may be rotational dynamics needed to answer that question. The only one that I can see for this type of solution is if there is a force pushing on the object up the hill overcoming gravity. Sorry I was not a lot of help. I hope are videos were still helpful.

[cr41gwoody]

Have you any momentum and collision vids up ?

[PhysicsEH]

@cr41gwoody Yes. Go to our page w w w physicseh com (add the dots in the right place because Youtube does not let me send links to videos ) This address is also in the description of the video. On that page you will find a set of 4 momentum videos starting with "physics lesson: momentum part 1" I hope you find them helpful.

[Cab00v]

Thanks a lot man. This is one video I'm glad to not "rape the replay button". =D

[PhysicsEH]

@Cab00v Thanks for letting us know. Glad to help.

[Zach6393]

I have my midterm exam in a couple hours and I just now am finding these videos, I will be frequenting this page and subscribing for future reference!

[PhysicsEH]

@Zach6393 Great. I hope they help. Let your friends know about them. Thanks.

[TheCelltick]

thank you, the group of people who made this, are probably the only reason i will pass my midterm thank you!

[PhysicsEH]

@TheCelltick Glad to help. Tell your friends.

[Smashing9882]

Thank you a million! Here's some stuff I learned!

(1) the normal force is NOT always equaled to mg.

(2) also had a hard time understanding what mg was...it's the force on the slant box (or the weight)not the power of gravity.

(3) how to break down the components of mg (tried by myself several times but had a hard time trying to do it since every problem had different scenarios)

(4) when finding force acting upon it always do both x and y components even though one maybe obvious.

[PhysicsEH]

@Smashing9882 Wow. I could not have summed it up better. Good work.

[pac4905]

i seem confused some how not quite sure how you got Fgx = mgsin30 = 24.5N can you please explain that? Thank You!

[PhysicsEH]

@pac4905 Imagine the hill is an x-axis and then split the Fg into components as shown in the video. One component is parallel to the x-axis this is Fgx.

The angle of the components is the same as the angle of the hill (30).

Now:

Sin30 = Opposite/hypotenuse.

in the triangle shown Fgx is the Opp and Fg is the hyp so

Sin 30=Fgx/Fg Rearrange this and you get

Fgx=FgSin30 and since Fg =mg you end up with

Fgx=mgSin30 Sub in m and g

Fgx=5*9.8*Sin30 = 24.5N

Hope this helps

[pac4905]

@PhysicsEH  thanks

[joshrichardss]

i am unsure why the friction is 15N

[PhysicsEH]

@joshrichardss Hi. The friction was given in the question so we did not calculate it. In later examples I think we calculate it.

[ThreeEscapeas]

THANK. YOU.

[Be1smaht]

Thank u... I'm taking my MCAT soon and reaaaaaaaly need this help so thanks again. Hey do u know what determines whether or not forces are conserved and what that means.

[PhysicsEH]

@Be1smaht Forces are not conserved (momentum or energy can be) but since the object is not accelerating in the y-direction then the Forces in the y-dir =0. Since it is accelerating in the x-dir then the forces add up to mass X accel or F net = ma is used in the x-dir. In this question, it is given that it will accelerate down the hill so that’s how we knew to add those forces up and ignore the y-direction. I hope this helps.

[DronElektron]

Thanks, very helpful! Good lesson

[Terrorera]

this is an excellent video. my physics teacher was not able to simplify it the way you did. thank you sooooooo much!!!!!

[anthonychemistry]

Everything is okay on this video but i am not sure about assigning the 30 degress on getting the Fgx and Fy component. What special angle or geometrical relation to assign 30 degress? are they transverse angles...etc... please make a follow up answer.. I was a great video but i need to clear up the angle..please.. u truly appreciate to hear your response..

[PhysicsEH]

Hard to describe in 5oo characters. Draw horizontal line from 30 degrees on the left to Fg to make a triangle with the horizontal, ramp and Fg. The angle at the top and just under the bottom left of the box is calculated as 180 (angles in triangle)- 30 (angle of ramp) 90 (right angle bottom right) = 60. Angle under box between x-axis and Fgy is 90 (right angle), Find the angle you want 90 the 60 (angle between x-axis and Fg) = 30 for the angle between Fgy and Fg

[PhysicsEH]

I posted an explanation. Im not able to put a diagram on it. Reply if you need more.

[gefferzz]

cool up load, thanks. keep it up!

[kikbalkid]

Thank you so much! This helped me review for my test. I appreciate the post :)