Newton's Second Law of Motion: F = ma
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- Опубліковано 2 жов 2024
- One of the best things about Newton was the way that he showed how natural phenomena abide by rigid mathematical principles. So much so that we can use mathematical equations to calculate how objects will actually behave. This equation, F = ma, looks pretty tame, but it packs a punch!
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I didn't want to study this shyt when I was in college and now I'm a drop-out. Now I'm interested in this thing. Love this life ☺️
lol
Gotta get thos brein pts. amrite?
Hahahaha ikr. 😆 life is really weird. Full of shit 🤣
☺️
Public colleges are still a great option. Have you considered that?
and i still dont understand 💀
my teacher complicated this but you just showed me that it’s easy, give her teaching lessons please x
oooohhh! HAHAHAHAAH
Same
My teacher told me to watch this video she didn't explain anything.
Hi Prof! My teacher said that the more correct version of the second law is F = (dp)/(dt) * k ..where p is momentum ofc..and the statement of the equation as per my teacher goes-- the force applied on a body is directly proportional to the rate of change of momentum. Well, of the three laws , I find the second one trickiest of the lot , so I could really use some detailing on this if you may. Thanks for all your in a nutshell videos!
oh no. I'm still in 11th grade please don't tell me this gets more complicated TwT
Do you know what this means, F = - F
I saw it in a video and was wondering if it is related.
@@henshuteamv4760 dont worry, professor is there to simplify it for you
If Mass is const:
F=(dp)/(dt)
F= mv (d)/(dt)
F=m (dv)/(dt)
F=ma
If Mass is variable but velocity is not
F=v (dm)/(dt). [P=mv]
If Mass and velocity are variable
F=(d)/(dt) (mv)
[Differentiation Product Rule]
F=m (dv)/(dt) + v (dm)/(dt)
F=ma + v (dm)/(dt)
@@EyeswideOpen22I think it just refers to Newton's third law where the force F of object A on object B is equal but opposite to that of object B on object A (written as -F)
Now I remember why I don't enjoy learning physics.
I enjoy knowing and understanding physics but learning it is painful.
What a contradiction
The logic is fun but the math is a pain
In class i be like🤔🤔🤨😪😶🤔🤔🤔🤔😪😪😪
It isn't that hard for me but it ain't easy, the only problem here is the confusing (2.3m/s²) and 20.0 N = m (0.77 m/s²) I suck at Maths
@@miscl_anon *This*- so much this! imo unless you're part of the
F = m a
m = F / a
The units for force is the Newton which is also expressed as Kg meter / s2
∴
m = (20 Kg meter / s2) / a
The final velocity is 2.3 m/s
The acceleration means change in velocity:
a = (2.3 meter / s) / 3 s
∴
a ≅ 0.77 meter / s2
For each second that goes by, velocity increased by about 0.77 meter / s
m ≅ (20 Kg meter / s2) / 0.77 meter / s2
m ≅ 26 Kg
Hi... Can you help me with my module..
Ty
@@jellieshaynetagumpama9077 xD
fuck it i dont get it
how did u get the 26 kg
I wish his solving would be more detailed, it'd help a lot. I do appreciate the style of his videos, but this one specifically kinda felt hard to follow. No hate though, just constructive criticism! I adore his work.
I wanna be Professor Dave in Halloween. He's LYFE.
haha there should be a prof dave costume! it would just be a wig and a beard and a flannel shirt though.
GENIUS
this guy deserves way more subscribers .
i agree! spread the word :)
no he doesn't
hahaahahahaahaa
ItsYeBoiChase Y
what kind of math was used to find the mass??
as an Egyptian girl I really really like your video...you're intelligent Dave!♥
This guy is better than crashcourse
Crash course big gay.
True 😁😁😁
@@c.darwin9259 no, crash course bigger gay
Denim ha, side note I don’t actually think there bad, lol.
You're true
Dear Professor Dave,
We are writing on the behalf of our 6th grade class and we just wanted to let you know that we are watching your videos on Newton's Laws of Motion and we are really enjoying them. We were wondering if you could do a zoom session with us and answer some of our classes questions.
Sincerely,
Linda Carlesi from the Stevens Cooperative School
Your never going to get an answer from him commenting on a video made 6 years ago.
Lies again? Marine Soldier Special Forces
F = m×a
A 6 foot 3 inches tall and 5 foot wide and 1000 kg tempo is travelling at 18 m/s² calculate the force?
Answer explanation
f = m×a
Or f = 1000 kg × 18 m/s²
Or f = 18,000 N
Thankyou 🙏🥇🏅🎖️
Wait,... so F=ma. If I jump off a tall building from the attic, then F=mg with m is constant and g is constant so F is constant. That means there’s no difference between jumping off from 2nd floor and 20th floor.
That F you are referencing is your weight, and yes, your weight doesn't change as you're falling (or at least it only changes very negligibly).
@@ProfessorDaveExplains hi Sir. Add me with you. Please i wanna listen all about physics
@@ProfessorDaveExplains hi sir can you please add me I really need for memorizing all phisic please if possible proffeser
Conservation of momentum due to time and distance
You're a wizard. Thankyou for your ongoing magical content, stepping in where my lecturers don't
Waiting for an andhbhakt to claim it was discovered by ancient rishis 😂😂
Beta Jo ha wo Hai.... apna sa thnk Mt kr😊😊
first of all thanks a lot for everything Professor
secondly, can you present to us a video about "fluidization " ? please
Hello professor, I'm trying to write an equation that describe a point (Dimension 0) generating spacetime, like a planet generating an electromagnetic field. The shape is a donut 🍩 or taurus. But no hole in the middle, just a point.
And where every point on the donut is a protection of that singularity.
(Take a breath)
Every point is identical, the spacetime around it is infinitely varied.
What course do i need to write that so scientists can understand it?
Cool property of this theory: there is no matter, just warped spacetime. That is why we only find forces and interactions, no "thing".
It probably meeds some fractal equation too.
I hope you can guide me in my quest.
Thank you so much.
U explain very clearly and u deserve more likes
Mass of the cart is irrelevant because I'm strong. 💪
thanks for making everything easier!
. ok i didn't get his answer
You divide the velocity over time so you get acceleration then you plug the acceleration and force in newton's law
@@abodalashkar5686 So you divide velocity by the time??
(Bad english comment here)
Because you must get the "F = ma". And there is no 'a'. So you can use "V = Vo + at" equation(it is already we know in kinematic). There is no initial velocity (which mean Vo = 0), then add the number to the equation.
.
.
.
V = Vo + a.t
2,3 = 0 + a.3
a = 2,3 / 3 = 0,77
Uwalaa.... You got that
I thought before that his informative videos are full of jokes because of his profile that seems comedic, that's why I don't watch his videos. However, as I have tried watching them recently, I realize that it seems more informative that other videos: great presentations, great explanations, and great person. Excellent work, professor!
And thank you, sir!
When I read my Text book my mind has been blind. Now I understand all
Me too
im not christian so correct me if im wrong but does this guy look like the rendition of jesus in the bible, atleast somewhat
If no acceleration is there and only constant velocity then how to we calculate force.
The cart goes from rest to 2.3 m/s^2, so there has to be an acceleration since it changed states
Best explanations on youtube :) You´ve helped me a lot in organic chemistry especially :) THank you so much
burh, you edited the comment but still said "THank you"
@@superchessmachine burh
@@jakepanda3834 lol atleast I didn't edit the comment tho huh
thank you physics jesus
If a 10-ton truck were traveling at a constant speed of 70 mph, does F=ma suggest it has no force? I think somebody hit by that truck would disagree, if they could.
If the speed is constant and the direction is constant, then there is no net force. The traction force powering it forward would equal all resistive forces it has to work against. The normal force stopping it from sinking thru the asphalt would equal the component of its weight pulling it toward the road. If it were moving around a curve, it would also require a radially inward force to keep it on the road.
Technically it isn't moving at constant velocity, because it is also moving around Earth's curvature. But this is considered insignificant, unless you are specifically told to account for it, or if its speed is comparable to the escape velocity of Earth's gravitational field. All this does is make its weight slightly less. Look up the Eotvos Effect, if you are curious to learn more.
More of this move up head.....
I don’t get it and how would you calculate it one planets.
Wow, this took me 2 days to understand, and you explained it with in 4mins bravo thanks
This is highschool subject and me in 4th grade learning this
ŲwŲ
In your example at the end you took velocity to be equal to acceleration. Are they supposed to be different though?
acceleration is change in velocity over time, that's the first calculation
thank you Dave. This video helped me greatly.
Time affects Petrol consumption, why time doesn't affect force. I mean to say if 20 N force is applied for 3 secs, won't it be 60N😁
Petrol consumption doesn't equal force. Force is an instantaneous concept. Concepts like impulse and work are cumulative concepts that time would effect.
I sang along with the opening song in front of my roomate
2N would generate acceleration of 2m/s/s for 1Kg
4N would generate acceleration of 4m/s/s for 1Kg,we can see if force is doubled acceleration is also doubled, So Where is concept of if acceleration is doubled force will be quadrupled
I wish I didn't have to figure out the comprehension check by myself.
the formula for acceleration came to me coz duration and speed are probably important to know so that made sense.
Or I wish I knew I'm dividing 20 N by its acceleration of 0.77 m/s because that's the only way to get 26. I understand those are basics you should have to come in for laws of motion lessons, but this is also something an annoying, grumpy teacher would say
excuse me I am ask about (a) acceleration >>what about the (space) I mean if the value will be different in it
Oh, so in order for F=MA to work, at least with Newtons measuring the F, then A must be measured in m/s and M in kg?
acceleration is m/s^2
F=ma
F=20 N
m=?
a=v-u/t
To find acceleration
v=2.3 m/s
u=0
t=3 s
a=(2.3-0)/3
a=2.3/3
Now,
F=20 N
m=?
a=2.3/3 m/s²
F=ma
20 N=m × 2.3/3 m/s²
20 N × 3/2.3 m/s² = m
60/2.3 kg = m
26 kg = m
You push an object, and it accelerates. You push harder on the same object, and it accelerates more quickly. Yet, when you push just as hard on a heavier object, it accelerates much more slowly. Why ?
That's what this video is about. You should watch it.
Bro i was scrolling through ur channel and how many subjects do cover? U got everything from biophysics to Italian
The typical form of the force equation is
F(r, θ) = f(r)(i cos θ + j cos θ)
where i and j are unit vectors
This is the differential equation corresponding to F = ma, but i don't 100% understand it (like what is f(r)?)
m(r i cos θ + r j sin θ)'' = f(r) (i cos θ + j sin θ)
My 7th and 8th graders wanted me to let you know that the velocity in the test problem wasn't actually velocity because there was no direction. LOL! Thanks for helping us learn :)
Great way to say absolutely nothing, maybe try a walk through on solving the problem
Hey Prof
Does Force applied also depend on the shape of the body as you take a toy car and push it, it will go a distance "x" and invert it and check and push it with the same force it will go less distance . Thus the shape also comes in picture
hmm, i believe that's only the case because of wind resistance and friction and stuff like that, if you give the toy car a push in outer space, the shape will be irrelevant.
thanks a lot
I'm a year 5 and have no idea what he is saying I think this is year 11 stuff lol
Where are you from sir.
Really watching this video is the assignment for e learning, am i the only one who has to watch this
nope
he explains every thing so easily . great explanation
Thanks for the information
you won't get the answer easily unless you already know that acceleration is equal to change in velocity over time
Hi Prof. Dave, can you explain how did you get the 26kg mass answer in the question. It's kinda hard for me since I homeschool my son. Your video really helps me a lot. Thank you in advance.
just divide both sides by 0.77! Newtons are kg m/s^2 so everything cancels but kg
Oh thank you so much for your reply. Appreciated! God bless. I'm now a fan.
@@ProfessorDaveExplains what do you mean by both sides?
im just a student so pls help me
Pro Dave the question that always comes to mind is how Newton equate between force and mass x acceleration
He didn't really. Fnet = m*a is a modern interpretation of Newton's second law, expressed in a way that is easier to understand in an introductory context.
In his original work, the formula he really gave was Fnet = dp/dt, where p is momentum. Mathematically, this is equivalent to m*a, as long as the speed is insignificant relative to the speed of light.
Can this be used in feet and pounds?
How do I find the speed if I know that car1 has a weight of 2729lb and pushes car2 weight 3267lbs, car2 gets pushed 28ft
Pounds are conflated as both a force and a mass unit, which makes it more confusing. It is only valid for force pounds to directly be determined by mass pounds, if we are talking about weight in Earth's gravity. Forces in general will have no connection to mass, and F=m*a only directly applies if you use a consistent set of units. Our brain is not set up to handle force and mass in units that are not interchangeable, which is essential if we wish to understand Newton's second law, unless we have the luck of gravity being 1 unit/s^2.
For pounds to be the force unit, and ft/s^2 to be the acceleration unit, you need to use slugs as the mass unit. Most people in the countries that use this unit system, have never used a slug in their life. A slug is a unit of inertia, which is the mass that will accelerate at 1 ft/s^2, when subject to a net force of 1 pound. A slug of mass roughly weighs 32 pounds.
For pounds to be the mass unit, and ft/s^2 to be the acceleration unit, you need to use poundals as the force unit. Again, a unit that is Greek to most people who use this unit system. A poundal is about 1/32nd of a pound of force.
As a white male this video really tickled my fancy Jim.
I hope my kids enjoy this video as much as I do. They will also be white and names Jim.
hey professor!just a little suggestion. can u make vids on stoichiometry
i already did that, friend! check out the general chemistry playlist.
thank u professor
If I were going 20 mph and I hit a wall I prolly wouldn't die, but if I was going 100 mph and hit a wall I prolly would die, but in both scenarios I could feasibly have the same acceleration and mass, meaning the same force. But obviously hitting a wall at 100 mph I will feel more force. Can someone explain how there doesn't have to a velocity component in this equation as well?
The acceleration is not going to be equal between the two scenarios. Worst-case scenario, you have to come to rest in the same amount of stopping distance, which means the force will quadruple. Best case scenario, the impact force is linear-elastic, and the maximum force will be proportional to the velocity.
ok i gotta question cuz im dumb asf.. how did 0.77m/s squared became 26 kg?
edit; lol i got it now
Greater the mass , greater will be the force and acceleration then why a is inversely proportional to m
I have a very important 2 questions for me:)
1. In space, there is a space shuttle that does't move. Mass of this shuttle is always constant. This space shuttle has a rocket engine which produce a constant force of 100N. When the engine is started and the ship has a constant thrust of 100N, when the ship starts to accelerate, will the acceleration be constant and remain constant (let's assume 10m / s), or maybe the acceleration will start to decrease as the speed increases? It is related to the rule Ek = 1 / 2mv ^ 2 ???
2. Same space shuttle doesnt move. Shuttle start to accelerate from 0km/h to 10km/h in 5 seconds and it takes "X" energy for example. How much energy it will needed to accelerate also 10km/h more in also in 5 seconds when it allready have velocity of 100km/h ? Also "X" energy? Or much more "X" of energy? And why is that?
Good questions
1. acceleration will decrease to 0 and the velocity will be constant since it is in space. the space shuttle will continue to move in space
Question 1: A rocket is a system of varying mass. In order to be able to run the rocket engine, you have to lose mass, which means thrusters that provide a constant force will cause a continuously increasing acceleration while the mass decreases. Eventually it will run out of fuel and cease to be able to accelerate, at which point it will coast at a constant velocity.
Question 2: Not possible to answer without knowing the specific impulse of the propellant. I.e. how many Newton-seconds of impulse each kg of propellant provides.
amazing video! explained really well
I wonder what happens if him and Organic Chemistry tutor collaborate
I got 25.97kg. though I know you approximated the answer. Thanks
Clear and simple lesson! Thank you!
Professor Dave, Can you help me answer the question :" How many kilograms is a cow on a trailer if 1200 newtons of force are acting on it?" thank you. I am confused about some practices on web.
Not enough information. We would need to also know:
A: the mass of the trailer itself
B: the acceleration of the trailer
C: the context of the force in question. Are we talking about its weight, or the forward pulling force from the tractor?
D: other forces involved
This video is wonderful and amazing
a stone of mass 5kg falls from the top of a cliff 50m high and buries 1m in deep in sand.find average resistant offered by sand (the answer in the book is 2450N) and if i use the equation (mg-Fres=ma) the answer i get is 2499N COULD YOU EXPLAIN THIS PLEASE
accidentally deleted my other comment, are you referring to Force with "average resistant"?
ur the best
y,know first i thought you were a bill nye rip off but not anymore
Nice job. Would't hurt to change out of your pajamas, though.
That is a man’s flannel shirt.
Physics (F=ma) test: “Without” applying the Energy from within you, choose an object of your choice, and apply only the Force or Net Force needed to push it away from you or pull it towards you. Please let me know if you’re able to. This is only a test. Thank you.
Get a motor with a winch and turn it on so the tension in the winch cable pulls the object toward you. Technically, the energy didn't come from within me, it came from the battery that powers the motor.
Why do we use mg * sin a and mg * cos a? I don't seem to understand it
Hey professor, awesome videos, keep up the good work, thanks a lot for all your hard work, you are helping a first semester college student preparing succinctly for his upcoming organic chemistry exam!! Thanks! I have one question though: do you have any videos on inductive and mesomeric effects? If not would it be possible for you to upload a video regarding these two topics because i don't seem to really get the gist of it and these effects are quite important :/
Anyways thanks again and keep up the good work ;)!
in the organic chemistry practice problems playlist there's one on the acidity of carboxylic acids that talks about inductive effects a little bit, hopefully that helps, if not feel free to email me with a question and i will try to help!
@@ProfessorDaveExplains you deserve more subscribe, thanks a lot for describe ☺️💯
I have one question for this lesson , how that rhe changing in velocity mean acccelaration how do that happen? ☺️
So is it like a change of an objects movement, like a plane? So it move forward then starts moving upwards?
Professor Dave, Awesome!
kajsi nebricen
Newton's Second Law of Motion needs a slight correction since they did not know about squaring a number in Newton's era we can assume that this may have been overlooked. As such F=ma^2 is a natural correction that can be easily proofed through calculation, formulation, and experimentation. This correction is 33% more accurate if you do not accept it proof it yourself.
Uh... what? Newton developed calculus. He knew about exponents. Everything you have just said is extremely incorrect.
We've known about the Pythagorean theorem, the quadratic formula, Cardano's cubic formula, and the foundation of imaginary and complex numbers, all before Newton's time. There is no way they "did not know about squaring a number" in Newton's era.
This video hurts my brain but it was helpful
okay so i got everything until you lost me. I get that 20.0N = m (0.77 m/s 2) but i don*t get how that translates to m=26kg. Can someone pls explain?
Same ques
Yall gotta help me bro, my test is tmrw 😭😭
N can be rewritten as kg m/s², as per its definition. Replacing that in the equation allows us to cancel the "m/s²" part:
20N = m (0.77 m/s²)
20 kg m/s² = m (0.77 m/s²)
20 kg = 0.77m
m = 26 kg
Hope this made it clearer
I have always had this problem with this equation. F is defined with kg. Mass is defined with kg. Thus it seems to me to be a circular reference. Obviously I’m not understanding something. How is this NOT a circular reference?
Forces are expressed in Newtons. Mass (kg) times acceleration (m/s^2) = Newtons (kg m/s^2).
@@ProfessorDaveExplains Thanks for response. One thing I learned in engineering school is to always check your units to avoid a stupid answer. Using the units you state, the quation F-ma becomes:
kg m/s^2 = kg m/s^2. Sort of a truism! I know I am not getting something correct, but do not see where. I just love physics and try to understand things. But I still find this a "circular" reference. If you can point me to a fuller explaintion elsewhere on the internet then i will go there and try to understand what I am getting wrong.
Further: I always find it easier to understand this equation if you look at it this way:
m = F/a. Mass IS DEFINED as the ratio of the force it takes to accelerate an object at a certain rate. My problem is how to define force. Ingnoring relativity, we can measure time (s) and distance (m) anywhere.
That's a heavy a*s cart bruh
Why is it meters per second squared and not just meters per second. Like one newton is how much force it take to move one 1kg 1meter in 1 second. The squared part is throwing me. Is it because its acclerating and the squared allows the speed to go up maybe?
forces produce accelerations, go earlier in the series and review position/velocity/acceleration
@@ProfessorDaveExplains i learned its increasing on meter per second every second it all makes sense thank you :)
Arrived to learn about Newton's second law, stayed for the intro.
Can we use F=m.v/t?? It results in 26.08 kg..
Only if acceleration is constant, and we are specifically talking about change in velocity from rest or to rest. In general, the formula is F=m*dv/dt, and it is a calculus problem.
why does n/kg=m/s^2 unlike other formulae like V(m/s) = D(m)/(t(s). The units dont make sense for me in f=ma. Can anyone explain??
mass is kg, acceleration is m/s^2, so force is kg m/s^2, or Newtons.
@@ProfessorDaveExplains Thank you so much!
what the sigma am i right?
Cheesus has come to help
thank you sir dave this is our teahers told us
Awesome teaching sir
No idea
Sir F=dp/dt=d(mv)/dt=mdv/dt+vdm/dt= ma+vdm/dt .and not equal to ma only . DrRahul Rohtak Haryana India
When m is constant, it is equal to m*a. dm/dt would equal zero by definition. For non-relativistic systems, and systems that don't add or subtract a significant amount of mass (i.e. not a rocket), dm/dt might as well be zero. Mass is conserved, so unless there is a reason for an object to lose mass, its mass will be constant.
THANKS MAN AMAZING VIDEO YEEEEEEAEEAAAHAHHAHHHHHHHHHH!!!1!1!1 BOWWWLINGGGGGG BUNDALONG 4 LIFE
i am still 6th grade
it wouldnt be heavier object because we are talking about mass
Hi watching here from ph because online class haha
english
Thank you sir Dave for helping me thank you