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@@warrenpadilla2304 how is "you are a lost cause and stupid" supposed to be motivating..This teacher refused to help him and even told him to give up basically by calling him stupid and a lost cause. Refusing to help a student who is willing to learn and be better is not calling doing their job, its called being insecure and unprofessional.
DDAA the teacher could help after/outside of class more exclusively, ur answer is semi-valid, however nobody that would say such a thing to a student should be hired as a teacher.
@@warrenpadilla2304 A teacher's job is to teach students that they are bad but can get better. Not to teach them that they are bad and will never get better.
@Winston Apollo this guy and the guy claiming this works look like bot accounts and I doubt anyone fell for it but I wanted to give a heads up just in case
Had an entire mechanics exercise on this as graded homework without having ever been introduced to the concepts during a lecture. Thanks for what you do
In question 2 part c you ask what the linear speed of a point at the edge of the rotating disk is and just multiply the angular velocity by r to find this. Correct me if I'm wrong but would this not depend on where we are assesing the speed of the point on the edge? If it's on the bottom of the wheel then it would be 0, if its at the top then it would be 2v. You have to specify where to solve that part
In 10:50 isnt that the average angular acceleration? Even though the answer is the same when you find the average linear acceleration it is still wrong to use omega...you should use velocity in finding average linear acceleration
thanks, very helpful. one thing tho, i try to solve the question on my own so when i pause the video (on pc) the title shows up on the top and i cant see the question so you could maybe move the question statement a bit in future videos :)
For the first question at 5:59, I converted radians to revolutions first, and then solved for the angular displacement, but I got a whole different answer.
Many people wonder why radians do not appear when we have radians*meters. Here is an attempt at an explanation: Let s denote the length of an arc of a circle whose radius measures r. If the arc subtends an angle measuring β = n°, we can pose a rule of three: 360° _______ 2 • 𝜋 • r n° _______ s Then s = (n° / 360°) • 2 • 𝜋 • r If β = 180° (which means that n = 180, the number of degrees), then s = (180° / 360°) • 2 • 𝜋 • r The units "degrees" cancel out and the result is s = (1 / 2) • 2 • 𝜋 • r s = 𝜋 • r that is, half of the circumference 2 • 𝜋 • r. If the arc subtends an angle measuring β = θ rad, we can pose a rule of three: 2 • 𝜋 rad _______ 2 • 𝜋 • r θ rad _______ s Then s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r If β = 𝜋 rad (which means that θ = 𝜋, the number of radians), then s = (𝜋 rad / 2 • 𝜋 rad) • 2 • 𝜋 • r The units "radians" cancel out and the result is s = (1 / 2) • 2 • 𝜋 • r s = 𝜋 • r that is, half of the circumference 2 • 𝜋 • r. If we take the formula with the angles measured in radians, we can simplify s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r s = θ • r where θ denotes the "number of radians" (it does not have the unit "rad"). θ = β / (1 rad) and θ is a dimensionless variable [rad/rad = 1]. However, many consider θ to denote the measure of the angle and for the example believe that θ = 𝜋 rad and radians*meter results in meters rad • m = m since, according to them, the radian is a dimensionless unit. This solves the problem of units for them and, as it has served them for a long time, they see no need to change it. But the truth is that the solution is simpler, what they have to take into account is the meaning of the variables that appear in the formulas, i.e. θ is just the number of radians without the unit rad. Mathematics and Physics textbooks state that s = θ • r and then θ = s / r It seems that this formula led to the error of believing that 1 rad = 1 m/m = 1 and that the radian is a dimensionless derived unit as it appears in the International System of Units (SI), when in reality θ = 1 m/m = 1 and knowing θ = 1, the angle measures β = 1 rad. In the formula s = θ • r the variable θ is a dimensionless variable, it is a number without units, it is the number of radians. When confusing what θ represents in the formula, some mistakes are made in Physics in the units of certain quantities, such as angular speed. My guess is that actually the angular speed ω is not measured in rad/s but in (rad/rad)/s = 1/s = s^(-1).
9:13 Using the definition of Angular acceleration, Angular acceleration = delta omega/ delta time. Which means it's (2,5) = delta omega/18. Which means Delta omega = (2,5)(18) = 45. Since omega initial is zero, then 45 is omega final. Which to be fair, the video also said that omega final is 45. However, for part b, the video uses an equation that are not explained how it come about. If i didn't square the time and didn't divide it by 2, then the answer for part b would be different (this shouldn't work like this). Any explanation?
Because the 0.5 is the radius so he divided that radius over rad becase for every 0.5 m covered 1 rad have completed as well. With that he can cancel the other rad and have m/s which are the units for velocity.
So whenever Im converting from radians to revolutions my calculator always gives me something different from yours. My calculator is in radians but idk if thats the issue. For example when you converted 150 radians to revolutions I got 235.62 revolutions as opposed to your 23.87 revolutions. Pls help
normally if you do 150/(2*pi) you schould get the right awser. you did 150/2*pi . your calculater will do 150/2 first (so 75) and then multiply it with pi, in wich case you will get 235. so it's important to put 2*pi in between ( ) or else it won't work. (sorry for the bad english)
My guess is that actually the angular speed ω is not measured in rad/s but in (rad/rad)/s = 1/s. If we say that the measure β of the angle is θ radians, we mean β = θ rad, and θ is the number of radians (it does not have the unit "rad"). For emphasis we can say that θ is measured in rad/rad = 1, since θ = β / (1 rad) and θ is a dimensionless variable.
When we use mathematical formulas to obtain formulas in Physics, we have to know what the variables represent. What I consider a mistake, is present in the literature, it is not only in this video. Therefore, I will leave another comment with the detailed information to be examined.
I would like to point out at 9:17 you didn't input time in WoT, so it came out wrong. So if you put in the correct formula, 0(18)+1/2(2.5)(18)^2 = 423 rad
For part a) of the first question, could u basically just use the equation for period(T), as this is 5 mins and rearrange for 2pi radians, then divide your answer by 2pi?
Hello everyone , if somebody could help... as i have learned that we can't apply kinematics motion equations when acceleration is not constant. here in circular motion ,acceleration is not constant as of changing direction so how come we are applying those equations to find the answer, ,kindly advise please. thank you..
just read the given quantities with emphasis on the units then say it again and again. eventually you’ll think something is wrong because the unit for this quantity (say, velocity) should be in meters not centimetres
It means final X minus initial X. Which is the change in X. Which is the total quantity of X. The o means initial, the X with nothing implies final. Everything of a certain quantity is final minus initial.
@@cheeesonator hahaha thanks for the answers. I had my exam 2 days ago... and i dont know if i passed or not it was a difficult exam.... will update it xD
My guess is that actually the average angular acceleration α is not measured in rad / s^2. The unit is (rad / rad) / s^2 = 1 / s^2. When we use mathematical formulas to obtain formulas in Physics, we have to know what the variables represent. What I consider a mistake, is present in the literature, it is not only in this video. Therefore, I will leave another comment with the detailed information to be examined.
Theta is angular displacement The formula should be Theta = (initial omega × time) + (alpha × time squared) Yours is wrong because if you want theta as the subject of the formula, why would it be on both hand sides of the equation. And his formula didn't have the initial theta. It has the (initial omega × time)
There's no need to put t cuz the initial omega is 0, so if you multiply initial omega which is 0 by the time, you'll get zero cuz any number multiplued by zero is equal to zero
Hi, ineed your help, how were you able to get 23.87 on question number 3 letter a? I've tried it on many calculators now yet I can't het the same answers as yours...help please
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Saved my ass in Calc yesterday, about to save my ass in Physics and will save my ass in Chem tomorrow.
i have the same classes right now i better save my ass aswell
You are a God. My teachers refuse help me because they say I am a lost cause and stupid. You help me pass these tests and prove them wrong. Thank you
Teachers used to do that to motivate students like u..dont b mad at them..they r just doin their job🤗
@@warrenpadilla2304 how is "you are a lost cause and stupid" supposed to be motivating..This teacher refused to help him and even told him to give up basically by calling him stupid and a lost cause. Refusing to help a student who is willing to learn and be better is not calling doing their job, its called being insecure and unprofessional.
DDAA the teacher could help after/outside of class more exclusively, ur answer is semi-valid, however nobody that would say such a thing to a student should be hired as a teacher.
U got it mate
@@warrenpadilla2304 A teacher's job is to teach students that they are bad but can get better. Not to teach them that they are bad and will never get better.
You dont know how much this helps. May God bless you and give you whatever you wish for!
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I didn't get any help from my physics faculty, but I got you,and you helped me a lot to solve my problems in physics and made me understand better
How your teacher explains it: ~~~~~~~
How the OCT explains it: --------------------
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@Winston Apollo this guy and the guy claiming this works look like bot accounts and I doubt anyone fell for it but I wanted to give a heads up just in case
Thank you!!
I only got 3 questions wrong on my physics exam😎
49/56
Good job
Wow good job!!
My whole exam was 4 problems 🥹
whats the best way to study?! i need help, struggling in physics 1
@@TrumpPlays understand how the formula was derived
Had an entire mechanics exercise on this as graded homework without having ever been introduced to the concepts during a lecture. Thanks for what you do
I have exams on Friday. the only hope I have of excelling is this God-given teacher, thank you so much, Sir
Huge thanks for this video! Cleared up a lot of confusion I had prior to watching this.
This actually isnt that hard once its explained properly. Thanks.
No cause the fact that i didnt understand anything when my teacher explained it but understood everything 1:40 mins in is actually crazy. Thank you
Thank you even now your videos help's me a lot and um gonna ace this upcoming exams
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6:53 This had me confused and 18:26 this killed meeeee LMAO
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In question 2 part c you ask what the linear speed of a point at the edge of the rotating disk is and just multiply the angular velocity by r to find this. Correct me if I'm wrong but would this not depend on where we are assesing the speed of the point on the edge? If it's on the bottom of the wheel then it would be 0, if its at the top then it would be 2v. You have to specify where to solve that part
I do not know what I would do without you
This guy always manages to teach me
for the final question and final answer in revs, is it possible to find the time it is accelerating for?
yeh
Thus realy nice!!!!!!!! everything now is okay after watching this video
10:48 isn’t that final linear velocity formula? Is linear speed the same? I thought it be thetha/t (18 sec) no?
10:02 why no of Rev coming out wrong if we calculate it through wf omega final 45 rad/s
stoopid
It's the same answer if you use the final velocity
Your videos make me think that I like physics
In 10:50 isnt that the average angular acceleration? Even though the answer is the same when you find the average linear acceleration it is still wrong to use omega...you should use velocity in finding average linear acceleration
how about normal and tangential components of acceleration?
Thank you so much
I finally understand this... I'm so happy rn 18:54
I don't know what to say for you. You are a really brilliant thanks very much.
thanks, very helpful. one thing tho, i try to solve the question on my own so when i pause the video (on pc) the title shows up on the top and i cant see the question so you could maybe move the question statement a bit in future videos :)
same!!
For the first question at 5:59, I converted radians to revolutions first, and then solved for the angular displacement, but I got a whole different answer.
Many people wonder why radians do not appear when we have radians*meters.
Here is an attempt at an explanation:
Let s denote the length of an arc of a circle whose radius measures r.
If the arc subtends an angle measuring β = n°, we can pose a rule of three:
360° _______ 2 • 𝜋 • r
n° _______ s
Then
s = (n° / 360°) • 2 • 𝜋 • r
If β = 180° (which means that n = 180, the number of degrees), then
s = (180° / 360°) • 2 • 𝜋 • r
The units "degrees" cancel out and the result is
s = (1 / 2) • 2 • 𝜋 • r
s = 𝜋 • r
that is, half of the circumference 2 • 𝜋 • r.
If the arc subtends an angle measuring β = θ rad, we can pose a rule of three:
2 • 𝜋 rad _______ 2 • 𝜋 • r
θ rad _______ s
Then
s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r
If β = 𝜋 rad (which means that θ = 𝜋, the number of radians), then
s = (𝜋 rad / 2 • 𝜋 rad) • 2 • 𝜋 • r
The units "radians" cancel out and the result is
s = (1 / 2) • 2 • 𝜋 • r
s = 𝜋 • r
that is, half of the circumference 2 • 𝜋 • r.
If we take the formula with the angles measured in radians, we can simplify
s = (θ rad / 2 • 𝜋 rad) • 2 • 𝜋 • r
s = θ • r
where θ denotes the "number of radians" (it does not have the unit "rad").
θ = β / (1 rad)
and θ is a dimensionless variable [rad/rad = 1].
However, many consider θ to denote the measure of the angle and for the example believe that
θ = 𝜋 rad
and radians*meter results in meters
rad • m = m
since, according to them, the radian is a dimensionless unit. This solves the problem of units for them and, as it has served them for a long time, they see no need to change it. But the truth is that the solution is simpler, what they have to take into account is the meaning of the variables that appear in the formulas, i.e. θ is just the number of radians without the unit rad.
Mathematics and Physics textbooks state that
s = θ • r
and then
θ = s / r
It seems that this formula led to the error of believing that
1 rad = 1 m/m = 1
and that the radian is a dimensionless derived unit as it appears in the International System of Units (SI), when in reality
θ = 1 m/m = 1
and knowing θ = 1, the angle measures β = 1 rad.
In the formula
s = θ • r
the variable θ is a dimensionless variable, it is a number without units, it is the number of radians.
When confusing what θ represents in the formula, some mistakes are made in Physics in the units of certain quantities, such as angular speed.
My guess is that actually the angular speed ω is not measured in rad/s but in
(rad/rad)/s = 1/s = s^(-1).
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9:13 Using the definition of Angular acceleration, Angular acceleration = delta omega/ delta time. Which means it's (2,5) = delta omega/18. Which means Delta omega = (2,5)(18) = 45. Since omega initial is zero, then 45 is omega final. Which to be fair, the video also said that omega final is 45. However, for part b, the video uses an equation that are not explained how it come about. If i didn't square the time and didn't divide it by 2, then the answer for part b would be different (this shouldn't work like this). Any explanation?
You're literally a life saver 🌟♥️💓
you find theta by using W*T and anther times you used theta = W*t+1/2 omega *t^2 what is the difference?
I dont know but the second time the answer if we use w×t is 810 but when he used w*t+1/2omegat^2 it was 405....!?
11:35, why is it 0,5 over a radian?
Because the 0.5 is the radius so he divided that radius over rad becase for every 0.5 m covered 1 rad have completed as well. With that he can cancel the other rad and have m/s which are the units for velocity.
You really don't need to put the over 1 rad as it's always one, and anything divided by one is itself.
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For final angular speed we suppose to find Wf as we have W0, Alpha and Time. And you found Angular displacement instead.
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Very good explanation....
Very helpful! Thank you!!
So whenever Im converting from radians to revolutions my calculator always gives me something different from yours. My calculator is in radians but idk if thats the issue. For example when you converted 150 radians to revolutions I got 235.62 revolutions as opposed to your 23.87 revolutions. Pls help
multiply out 2 X pi manually first and then divide by that result and you should get the right answer. I had the same issue as you at first.
normally if you do 150/(2*pi) you schould get the right awser. you did 150/2*pi . your calculater will do 150/2 first (so 75) and then multiply it with pi, in wich case you will get 235. so it's important to put 2*pi in between ( ) or else it won't work.
(sorry for the bad english)
@@driesbrosens3089 I had the same problem, make sure 2pi is in parenthesis
@@lukasnolta9510 thankyouuu it seems like 2yrs ago but your comment helps me.
Make sure to put parenthesis around your 2pi!! I was having that same issue but adding the parenthesis seemed to fix it
Thank you very much!
My guess is that actually the angular speed ω is not measured in rad/s but in (rad/rad)/s = 1/s.
If we say that the measure β of the angle is θ radians, we mean β = θ rad, and θ is the number of radians (it does not have the unit "rad").
For emphasis we can say that θ is measured in rad/rad = 1, since θ = β / (1 rad) and θ is a dimensionless variable.
When we use mathematical formulas to obtain formulas in Physics, we have to know what the variables represent.
What I consider a mistake, is present in the literature, it is not only in this video. Therefore, I will leave another comment with the detailed information to be examined.
very useful, thanks
Sorry but where did you get the radius for example 2 @(11:33-34)
It’s in the question at the end in parentheses. He just converted from cm to meters
@@rulthlessrudy ohh my bad , didn't notice 😅
Thanks.
i love u teacher
How come for 1b you have to concert back to radians? Is theta not in degrees? And is revolutions always in degrees versus radians?
It’s because the big booty bitches couldn’t see me
I would like to point out at 9:17 you didn't input time in WoT, so it came out wrong. So if you put in the correct formula, 0(18)+1/2(2.5)(18)^2 = 423 rad
0 multiplied by 18 is still 0. The one in the video is correct
i have a physics exam tomorrow ill update depending on how well it goes
For part a) of the first question, could u basically just use the equation for period(T), as this is 5 mins and rearrange for 2pi radians, then divide your answer by 2pi?
Organic is the best
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Awesome 💯
Thanks!
This help me alot
Omega... I mean Theta......
(haha seriously tho love your videos)
Thanks my friend
Good stuff m8
love u my guy
3:17
3:54
Thank you
for question 2 part b cannot i just have used theta=angular velocity * time??
Godbless u huhuhu u save our lives huhuh usto mo hakdog libre ko? Huhuhuhu thank u huhu
Hello everyone , if somebody could help... as i have learned that we can't apply kinematics motion equations when acceleration is not constant. here in circular motion ,acceleration is not constant as of changing direction so how come we are applying those equations to find the answer, ,kindly advise please. thank you..
9:10 Wait why not use w×t instead ...
The answer comes out to 810 so it is wrong but why
Someone help...
I know this is late but w x t is what u used when the acceleration is 0, but in this case it's 2,5, that's why you use the other formula :)
Why did you assume the radius on the first question
anyone else stay the extra 30 seconds at the end to see if there was a post-credit scene like a marvel movie :(
thanks alottttt!!!!
Ugh I always forget changing the units....
just read the given quantities with emphasis on the units then say it again and again. eventually you’ll think something is wrong because the unit for this quantity (say, velocity) should be in meters not centimetres
Thanks.
Instead of 'd' my books says 'X-Xo'
its the same thing x-xo is delta x or distance
It means final X minus initial X. Which is the change in X. Which is the total quantity of X. The o means initial, the X with nothing implies final. Everything of a certain quantity is final minus initial.
@@cheeesonator hahaha thanks for the answers. I had my exam 2 days ago... and i dont know if i passed or not it was a difficult exam.... will update it xD
@@cheeesonator PASSED!!!
KoSTas M fuck yeah man! We’re all gonna make it brah
in question 3c where did the radians go 4rad/s^2 x .3m = 1.2m/s^2
My guess is that actually the average angular acceleration α is not measured in rad / s^2.
The unit is (rad / rad) / s^2 = 1 / s^2.
When we use mathematical formulas to obtain formulas in Physics, we have to know what the variables represent.
What I consider a mistake, is present in the literature, it is not only in this video. Therefore, I will leave another comment with the detailed information to be examined.
instead of d =vot + 1/2at^2 my book says x=Xo+Uot+1/2at^2
awesome
Love you man
Why did you use ¢= (Wo+Wf)t/2 instead of ¢ = Wot + (at²)/2
my teacher is making me watch this
why didn't we use theta=omega t in 2nd problem to find revolutions>?????
For question 2, my formula sheet says theta=initial theta + omega t + 1/2 alpha t^2. Yours didn't have omega t. Someone explain please :)
Come again please. I can't seem to understand you.
Theta is angular displacement
The formula should be
Theta = (initial omega × time) + (alpha × time squared)
Yours is wrong because if you want theta as the subject of the formula, why would it be on both hand sides of the equation.
And his formula didn't have the initial theta. It has the (initial omega × time)
There's no need to put t cuz the initial omega is 0, so if you multiply initial omega which is 0 by the time, you'll get zero cuz any number multiplued by zero is equal to zero
The goat
I love you
Lub u Sir
Lub?
Did everyone get 64 revolutions for 2b?
Hi, ineed your help, how were you able to get 23.87 on question number 3 letter a? I've tried it on many calculators now yet I can't het the same answers as yours...help please
1rev = 2pi rad
@@user-oh3lc2ls7d thank you
@@michaelaong1174 no problem, I was confused too
so you are stupid
vevolution
❤
Saving my ass again.
Noice!!!
I guess you missed the t from ex.2
The angular velocity is 0 so it would've canceled time out
you are not giving us the formulas to solve this. you never gave us Wf=Wi + alpha t
that was like the second equation he gave wdym😭