Does the Book Move? An Introductory Friction Problem

[@McTheWarhammer]

Just found your channel, as a physics student and someone who loves physics, your videos are great!

[@FlippingPhysics]

+TheWarhammer Glad you found me. Thanks and believe it or not, I also love physics. 😄

[@rogergordon63]

the way you teach is awesome

[@FlippingPhysics]

+rogergordon63 thank you.

[@rocks813]

I was about to recheck my solution for Question B (I try to answer your problems before watching you solve it) because I had a different equation than the one presented in A. But I watched on. Ha, the solution to Question B was very, very vindicating. Enjoyed learning with you, Mr. P!

[@zeroblade8315]

Great vid really helps, but I have a question. When doing questions like this do you usually assume the given coefficient of static friction is the max?

[@FlippingPhysics]

No. Typically we assume the _force_ of static friction is at its maximum. Please watch: www.flippingphysics.com/tire-friction.html

[@renanaraujom]

You are amazing, man! Congratulations!

[@FlippingPhysics]

Renan Araujo Thanks for the positive feedback. It feels good.

[@renanaraujom]

Channels like yours change the world. Keep it up, man. PS: I am from Brazil heheh

[@FlippingPhysics]

+Renan Araujo Thanks! You know, you can help me change the world by translating Flipping Physics captions to Portuguese. :) www.flippingphysics.com/translate.html

[@renanaraujom]

Right! I am gonna see the link. Best regards!

[@jobellegenio149]

i enjoyed watching and learning with you mr. p! the students were funny hahaha

[@FlippingPhysics]

makes me happy to know!

[@Interventionroblox]

Hello to all the members of Mr Alexanders 9th Grade physics class! 3rd Period is obviously the best period.

[@scienceseeker8377]

Please help me When an object is moving and accelerating When Do I type this equation F = Ff ????????

[@shauryasingh9553]

Hello Mr.P! Just wanted to ask why was there a spike when it changes from static friction to kinetic friction

[@FlippingPhysics]

I demonstrate that here: www.flippingphysics.com/friction-graph.html

[@seanbedel7694]

At what point do you know when to switch from static friction to kinetic friction in your equation?

[@Adumbb]

very late response but when you know it’s accelerating since kinetic is less than static so you can switch

[@mustafaRoya]

Fantastic You're the best physics teacher mr p thank you so much

[@FlippingPhysics]

+Gholam Mustafa Ali You are so much welcome.

[@isot6805]

Love your videos! Thank you so much for making these

[@harshitagrawal4368]

thank you...i like your videos.....they are very interesting and have helped me lot......happy teachers day sir

[@FlippingPhysics]

+hardik gupta You are welcome. It pleases me to know I am helping you learn.

[@harshitagrawal4368]

sir could you please explain banking of roads

[@saishiva8627]

well , i can do that in an another way . f = us x n = 0.27 x 0.674 x 9.8 =1.738 as 1.738 is less than 2n the force exceeds friction and moves . f = uk x n = 0.24 x 0.674 x 9.8 = 1.6 can u plz tell me where am i going wrong

[@FlippingPhysics]

+austin snow A KZbin comment is a terrible place to have a conversation about equations, but here goes... f = us x n : Which force are you talking about? is "n" force normal? assuming "n" is force normal, why does it equal 0.674 x 9.8, which I have to assume is the force of gravity which equals mass times the acceleration due to gravity. f = uk x n : Which force are you talking about? I don't see where you determined the acceleration of the block.

[@saishiva8627]

+Flipping Physics i am sorry , forgot to calculate acceleration . i have or it , then uk x n - f = ma abd then find a . sorrry i was more enthusiastic in doing sum rather than watching the video . sorry

[@FlippingPhysics]

+austin snow As far as I can tell, your solution is missing the following steps: 1) Summing the forces in the y-direciton to prove Force Normal = Force of Gravity. 2) Before you know the book moves, summing the forces in the x-direction to show that the force applied minus the force of static friction is positive and therefore the book moves. My approach is more general than yours, which is my goal. I am always trying to make my solutions more general so students can understand more complicated problems later.

[@saishiva8627]

Flipping Physics i am sorry , i am a physics lover , and i am always like finding simpler ways or faster so that i can do more problems and get accurate which has always thrown me in trouble . i am ur studeent now , i will take care . sorry

[@FlippingPhysics]

+austin snow Makes sense. No apologies necessary. I know it may seem counterintuitive at first, however, the more slowly and carefully you walk through problems, the more you will understand and the more quickly you will be able to solve problems. Trust me, it makes sense in the long run. Thank you for being my student. Keep up the good work!! Actually, I would suggest you watch this video of mine and keep the ideas presented in the video in mind as you work on _understanding_ physics. 😀 www.flippingphysics.com/understanding.html

[@albanmorina8630]

Hello, I'm from Germany. I like your videos. I'm learning english and physics at the same time. Could you please do a explanation of the special relativitytheory? Thank you :)

[@FlippingPhysics]

+Alban Morina That is great! Good luck with your dual learning. I am not going to do a new video about The Special Theory of Relativity for quite a while. You are welcome to enjoy my in-class lectures about it if you would like. kzbin.info/www/bejne/qKipd3R_jMeWitk

[@felipea.barretto7503]

+Alban Morina I'm trying to do the same thing with german! Can you tell me some good science german channels on youtube?

[@sivakumarsiva1743]

Why did you use maximum static friction to figure out whether book moves . You could have used kinetic also

[@keithmcleod3383]

The book starts from not moving. If you solve using the kinetic, you're starting from the assumption that it was moving. The static friction is greater, so you actually require a greater force to get an object moving. Once moving, the friction is reduced to the kinetic coefficient, and the acceleration is then greater. If you applied a force of 1.7 N in this case, the kinetic coefficient offers an acceleration of .17 m/s2. BUT, you haven't overcome the static friction first, so the book will not move.

[@sivakumarsiva1743]

@@keithmcleod3383 thank you

[@ughhash5853]

@@keithmcleod3383 he used kinetic friction to solve it right? and the answer is 6.1m/s^2

[@DanielLovesPiano]

@@ughhash5853 yup (after bobby used static, incorrectly)

[@MonkeyTune999]

Please come teach physics at my school we need you

[@prashantozapurna]

Excellent sir..