Work and Energy - Physics 101 / AP Physics 1 Review with Dianna Cowern

[@mxcollin95]

It’s been almost 20 years since I studied this stuff in school and it’s been a lot of fun to knock some rust off in remembering these concepts! You’re a great teacher! 🤙

[@josephmiller2573]

You are very "brave " by placing yourself in many precious positions.

[@kendavis8046]

While in high school, many decades back, I went to a gathering (I cannot remember the name of it, but I was there) held at the campus of Texas A&M. We'd discussed "Foucault's Pendulum" in our high school physics class (two years!). They had one on what I recall was on something like an 80 ft pendulum. We observed it when we arrived, and then observed it again at the end of the day. It wasn't moving horizontally as far, but naturally you could see the change in the arc. Great demonstration then, and great demonstration in this video. Thank you.

[@PapaFlammy69]

It ain't much, but it's work :v

[@hnnagarathna7286]

Papa flammy on Diana's channel???😑😑😑

[@outofbox000]

Simp

[@bhmangoz6396]

@@outofbox000 shut up he is not a simp Mr. Ghandi

[@math_the_why_behind]

I love how you do demonstrations to help explain a concept!

[@jamesbrock6278]

This series of videos is so helpful, and inspirational! It has helped me so much through my first year in physics! I would love to meet the person who wrote them.

[@sudheerthunga2155]

@Allu Baba Sai Harsha Patreons have early access ig

[@mastershooter64]

@Allu Baba Sai Harsha KZbin doesn't update view counts, like counts, the amount of time passed after a comment/video has been posted regularly so things like this happen

[@xandercorp6175]

@@mastershooter64 You need to read your comment back to yourself and figure out how to say it better.

[@xandercorp6175]

@Allu Baba Sai Harsha Channels can announce their videos in advance as a placeholder to advertise upcoming content and allow people to set a reminder, and people can comment on this placeholder; in this way, when the announced video is finally released, it can have comments older than the video itself.

[@p_square]

This series is growing exponentially interesting!!!

[@llaauuddrruupp]

These videos help me get through being housebound. No joke, I enjoy them so much.

[@MoMM-m1u]

The Drissor literally lighten up my day. Woke up today with a bunch of homework and finally get to watch this video during lunch time.

[@Vlashel]

Energy does not exist. I think this is not stressed enough. Energy is an abstract concept to describe and quantify interaction between different physical phenomena and matter. Objects do not have energy as a 'thing'. People always talk about energy like it's some separate entity inside of things that can flow in and out of things, but it's not. What we call energy is simply matter interacting with other matter. I wish the term was never used because it is very misleading, always calling it 'work' would be much better.

[@Vlashel]

@xrm160xqw I also said about interaction between matter and physical phenomena, light is electromagnetic radiation and it is a physical phenomena. Break down the sentence 'light is a form of energy', what is it really trying to say? Definition of energy from Wiki: "In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object." So, 'light is a form of energy' is really saying 'electromagnetic radiation has a quantitative property to heat or perform work on other objects'. Energy is a *property* of things to do work (interact with other objects to heat them or move them), but it's not a thing on its own, for example, there can never be such a thing as 'pure energy', because it does not make sense by definition.

[@portfolio2259]

"She's Moooven" such a great line. Good video as always.

[@choedzin]

When I first learned about work in high-school physics class, I was most impressed by the fact that if you push with all your might on a very heavy object without being able to move it, you've done absolutely no work at all, according to the meaning of work in physics. After that, I just felt exhausted. :-)

[@casparvoncampenhausen5249]

Well, that's in Physics land, where friction isn't a thing, sadly on real life this isn't the case

[@michaelsommers2356]

@@casparvoncampenhausen5249 Friction is why you can't move the heavy object. And since the object doesn't move, _Δx_ is zero, and the work done is zero.

[@chinmaykrishna6485]

This is taught in the 5th and 6th grades in India, at least according to the CISCE curriculum.

[@choedzin]

@@chinmaykrishna6485 It may be in the US now, too, but I had it in 11th grade in 1963 :-)

[@alvkarthik2018]

it's true, understanding energy was so difficult for me at first but thinking for 4-6 hours made everything sense. I feel, there is a huge difference between understanding something and knowing something.

[@iAm_Rohit_Raj]

I got the notification when I was looking for a video like this. Thank You very much!

[@TommyCallaway]

Science is awesome. Great work Dianna!! I'mma go life my cow at a constant velocity, will report back. :)

[@amritasingh8653]

I love this series 🔥 It made me love physics

[@herambpatilofficial]

@Mr Unknown We can call it series my friend, that's why it's called AP Physics 1 review

[@bobvines00]

These videos bring back a lot of memories! ;) Please turn on "closed-captions" though -- my hearing has deteriorated enough that closed-captions help me not miss some of what you are saying. Thumbs up!

[@darshandhamale7449]

My favorite channel on KZbin

[@TheDeerInn]

I know you probably won't respond, but did anyone doing the dropping ball test determine if there was a heat exchange resulting in a temperature increase in the springs of the trampoline? Using a thermal camera would be really cool to see the changes in the trampoline and the ball. No wonder I had so much trouble with formulas, no one ever explained how the exchangeable components, ie. J and Kg. Thanks for explaining it.

[@itsreeah2663]

I love your videos. Sending virtual hugs from a fellow science of CEst girl

[@itsreeah2663]

Thank you physics girl lots of love from the UK❤️❤️❤️

[@samedwards6683]

Thanks so much for creating and sharing this educational and entertaining video. I hope that each day you are feeling better than the day before 🙏

[@themrdeadlift]

Can we just take a second to appreciate how organized his shed/garage/workshop/ or whatever is? Wow.

[@nerdgeeknation8382]

One of these days Diana is going to be a famous physic icon.🤩🤩🤩🤩

[@Taran72]

That was awesome! It's definitely a nice way to revisit these concepts in a fun and intuitive way. I'm an engineer and after 20+ years of practicing I realize that putting my attention back to basics gives me a better understanding of what I'm doing. Would be interested in seeing a video on net force and why we use averages of physical quantities to evaluate real.problems. I will look in your video library.

[@Magicalfluidprocess]

You are exactly what this subject needs 👍

[@deepakjoshi823]

Hi Ms. Dianna I'm Deepak Joshi from India an ardent fan of yours! I too like Rihana's songs. He He😁😁 Lots of love and my respects to you! ❤🤗🙏🙏🙏

[@arunpandey7785]

The series of whole vedios are exponentially helpful !!

[@mrjoshmtz97]

Your videos are great! Plus I like science and physics as well. 🧪

[@bezbezzebbyson788]

The clearest explaination for it I found is this: It's a conserved quantity of a system with respect to time. The total energy of a bouncing ball is equal to a term containing its velocity (KE) and another term containing its position above the ground (PE). So since these 2 terms sum up to consonant if the velocity increases the hight decreases and vice versa which totally describe the bouncing ball system. That's way for me at least I love to understand the work-energy-power concepts starting with energy not work. Work is the change of energy. So in our system the change of KE between 2 points is the work between them (remember the total is consonant). And since any increase in KE comes from PE for TE to remain consonant. The work W describes how much PE was converted to KE from point 1 to point 2. From this you get that power is just the rate of this transfer (how fast it was) by dividing over the time from point 1 to point 2.

[@dharmeegajara440]

I can't thank you enough for making a video on ENERGY! the way you defined G.P.E. is what makes you physics girl!!

[@alexandergilling2813]

im studying for a AP physics test, and this was so so so so so so so so so helpful, ur amazing thank you

[@fullfungo]

There is actually a cool but high-level definition of energy involving symmetry, conservation and Noether’s theorem

[@Petch85]

what I like to mention when talking about "gravitational potential energy" is that if you do not want to damage stuff, you have to get rid of a lot of energi when you are lifting something back down to the ground. Thus if you are smart about it you can e.g. replace a wind turbine gearbox without using a lot of energy. Or you would have to dump all the energy into big radiators to get rid of all the energy without damaging stuff :-)

[@John-ci8yk]

Thank you for the time and effort you put into all your videos, thumbs up.

[@habibaelhadad1000]

I really like your own way of teaching, acting, n simplifying

[@BooBoo314159]

Hi Diana, nice video 😊, but I have a question about your 10kg space cow: You computed the change of velocity of the cow by choosing a reference frame where the cow is initially at rest. But then if I compute the change in kinetic energy of the cow from a reference frame where the cow is initially moving at say 10m/s, and knowing that the final velocity should be 24m/s according to your calculation in the video, I get the following: 0.5*10*24^2 - 0.5*10*10^2=2380J, which is more than twice the 1000J of the video. I find it a bit weird that the change of energy depends on the reference frame, and here is why: If I take my 1000kg car initially at rest, and I make it accelerate so that it reaches 14m/s, then its change in KE is roughly 100kJ. But if i do the same calculation from the reference frame in which my car is initially at 10m/s (say from some bicycle point of view) then we get roughly 238kJ. But if I assume that the energy comes from the gas consumption of the car, and assuming that the gas consumption does not depend on the observer, then I would expect that the change in KE should not depend on the reference frame (the observer)... I am missing something? Also, if the variation of KE does depend on the reference frame, how do I know which one to pick to estimate my gas consumption for example? I think I am missing a piece of the puzzle in here 😔🤯

[@lakshman.n9817]

Thank you for the kinetic energy that you transferred to me DIANA. This series of lessons deserve a dope salute.

[@Amansingh-wj8vj]

5:00 you can just doing magic with f=ma , s= 1/2 at^2=v and you can simply prove work formula. your mehod of explanation is really osom . Now my concept is much clear regarding work and energy . Keep it up

[@gopikrishnamaji536]

She's really a good teacher.. even MIT subscribes this channel

[@saadhassan8813]

I just love the series The videos are soo helpful

[@minguk0914]

I love you ❤️ physics girl you are the best physics teacher. Thanks to you I succeeded in the bac

[@localtitans4166]

Maybe the best physics classes in KZbin 😊

[@Godsgirl4278]

You're responsible for conservation of interest in Physics after a bad time with problems! Love from India:3

[@ajaykumarupadhyay5863]

Miss Dianna mam me Nikunj Deep is your daily viewer you are my favourite physics teacher plz make video on radioactivity it's my humble request

[@moharjyoti]

These needs to be on Netflix it's that good!

[@preetul]

people like you really inspire me to keep physicsing!

[@AlexNH56]

Yo thank you for this vid! I learned some more. I’m taking it for my first time ever in life and I’m close to my 30s in college so this is definitely something new for me

[@dstrome]

With the wrecking ball falling on the trampoline, how do you determine how much energy was transferred to heat vs energy transferred to air molecules? Is it correct to say that the example in the video didn't take that nuance into account during the calculations for simplicity's sake?

[@martf4701]

The important notions to remember about her videos are.. - the sound a rocket straped to a cow makes.. - and the ultra high speed that she tries to make us understand all her math formulas ... ( i always end up giving up trying to understand, even after replaying 3-4 times the video ). But seriously, who really give a damn about what she says.. She's just so god damn cute...

[@pierreabbat6157]

So friction is a liberal force? If you multiply a newton by a meter in the same direction, you get a joule of work. If you multiply a newton by a meter in a perpendicular direction, you get a newton-meter of torque. If you add torque and energy, you get a quaternion. Does this quaternion mean anything?

[@jlpsinde]

Amazing video, really great. I teach physics and with you I learn new interesting ways to explain.

[@dego28dego]

MARRKKKKKKK!!!!!! Still waiting for a collaboration between and the big KZbin physics and engineering people (Mark rober, dianna, vertasium, smarter every day, etc etc.)

[@Rubrickety]

7:20 “Let’s use our new tool!” So disappointed you didn’t mean the drizzors...”

[@khushichahal692]

Thank-you so much for your efforts. You made me fall in love with beauty of physics.🤗

[@k-2d]

ahhhh thank you so much!! I have a test on some of these concepts in a couple days and my final exam coming up too and this was a great review!!! will definitely be watching the other lessons aha

[@nvrumi]

This was fun. Thank you. You have very nice hand lettering. I'm quite impressed.

[@Magicalfluidprocess]

Hi Dianna can you do a vid on the double slit experiment?

[@namrofni6236]

Is there a channel like this for chemistry?

[@astrophiledevansh898]

Periodic videos is a good one

[@backstreetfan2887]

Professor Dave Explains, Bozeman Science, The Organic Chemistry Tutor, AK lectures

[@bassanup]

first time ever I'm not late for physics class.. :)

[@harshbamane17]

Mam ur funny character is terrific . Even coming first in class I have came here to learn it again from u mam. Thank you.

[@harishravishankar]

Great work \Del\crossE=-\partial B/\partial t 27.34. Best wishes :) Hope you keep inspiring. So many amazing videos. I do my work watching you everyday. Its my strength and you provide it. So we keep the relay going. I am a liker and commentor nowadays. MIT is great too. :) I did a lot from app inventor and my prof was from there too. I traveled there for orientation.

[@michaeljean1567]

Hey Dianna, The International Baccalaureate program would likely be a nice add to your video titles.... ie: Work and Energy - Physics 101 / AP / IB ...... Just a thought. MJ

[@charles_wipman]

I see it all "more clear" as visual example in flight sims like the DCS seeing how the missiles loose energy as they maneuver predicting where their target gonna be, once they've depleted the fuel, and change direction of your plane use to be enough to dodge or turn that missile into a paperweight; i always think on you on those situations, or when i see a space rocket going up, and i wonder how much weight must be that rocket loosing/burning as it goes up fighting the changing cross winds and the gravity while the air becomes thinner.

[@ronaldbucchino1086]

I used mgh when helping my son make his cub scout Pine Wood Derby car -- all had the same potential energy -- so it all came down to u or friction so lift one wheel from the ground and polish and lube the wheel axels -- LOL A winning strategy based on physics

[@Nareshkumar-dw9wz]

Amazing class Ma'am this video is so useful for us

[@traseag5793]

👍🌞👍 'Energy' is everything... Hence, Everything is 'Energy'... 🔅 ThankQ for your energy!

[@skarrambo1]

I'd answer the question, "What is energy?" with "The capacity that a mass has to move" - this is obviously ignoring waves/wave-particle duality, but given the target audience for this and the scope, I think this is contextually acceptable. The broader answer of course becomes more difficult to describe in a capacity other than mathematically.

[@zpader]

Mooooving got me. I love these videos!

[@TheCimbrianBull]

🐮 🐄

[@tirbelain]

You should have put two rockets to the cow. With this off-center thrust, the cow would not come very far and probably get really dizzy. ;) Actually I am a bit confused right now. Work is measured in Nm. But torque, which is a force (or isn't it?), is also measured in Nm. How are these two related?

[@J4-kjtdr8775]

Your a wonderful teacher that's for sure

[@Marvin_Maverick]

Splendid: "what's the rocket noise?" Noise? In space? Really? I like it, when people get overwhelmed by everyday experiences: Everything makes a noise, that's so true, nobody thinks about it twice. That happens to my also, of course! Oh, and: I like your video!

[@Magicalfluidprocess]

Time and space are functions of ones conceptual scheme

[@hermanjohnson9180]

I thoroughly enjoyed this.

[@mcconkeyb]

When do we get to the lesson where we talk about the fact the g is not constant? These problems only work out for changes in height that are small, where the change in g is so small it can be ignored.

[@shaungovender7805]

If I understand this correctly Work and Torque have the same units (Newton-meters). But for work a new unit was made (the Joule) and for torque the units were left as Newton-meters. Seems a bit strange... If torque and work have the same units does it mean they are the same thing?

[@daviddavids2884]

at 3:41, like everyone else, you ignore Rotary mechanical energy and the fact that it is SCALAR. eg., continuous. where mechanical energy is ROTARY, joule is not the correct metric.

[@POTATOEMPN]

Can you do a physics course? I already graduated years ago, but I could listen\watch you teach this stuff for hours on end.

[@FreemanVashier]

Great lesson!

[@TheCommuted]

If the Earth got smaller with no change in mass, using relativity, would there be a change in orbital time around the sun? Thinking about missing leap-seconds. Or, does the earth cooling slow it down? (Global warming, or not cooling as fast)

[@osmosisjones4912]

Wouldn't vibrating wall sending election through wall in a certain direction . Would heat up and melt them but a conventional rocket would push forward and energy going through walls would make it Easier on rockets. Also if much of a ships mass is fluid. The i guess panels on wheels with the fluid within pipes would move mass.

[@megamanx466]

Please word your question better, because I can't figure out what you're trying to ask. 😅

[@ReyLotsoFrancis]

She is the physics teacher i never had😁

[@Icouldbeaprettygirl]

So energy is the ability of any object to do work?

[@mihadbinislamtanim6267]

Diana: beans and rice, an exploding watermelon, and EXCITED DIANA Me: No! That's a perpetual motion machine constantly doing work.

[@dharmeegajara440]

Please make one on electricity too, both static and electromagnetism

[@konstantinkurlayev9242]

Thank you and get well please!

[@dylanparker130]

Dianna's cow must be in a constant state of terror! Cow: "Oh moo, what now?"

[@astrophiledevansh898]

Why work is calculated in terms of displacement and not in distance.

[@astrophiledevansh898]

This is my doubt

[@keshavb3128]

Can you do videos on the US Physics Olympiad (USAPhO) and the International Physics Olympiad(IPhO)?

[@shankarthiyagaraajan1147]

Thanks a lot. I learned new today.

[@SwordQuake2]

17:29 well you're applying a force to the cow over a distance. That distance is the same. The extra work is evidently not stored as PE but what is it?

[@michaelsommers2356]

I think you have the wrong timestamp. There's no cow at 17:29.

[@megamanx466]

Actually it is. The speed at which an object falls increases as the distance it falls also increases. The height that she has the cow basically determines it's potential energy. "Since the gravitational potential energy of an object is directly proportional to its height above the zero position, a doubling of the height will result in a doubling of the gravitational potential energy. " www.physicsclassroom.com/class/energy/Lesson-1/Potential-Energy#:~:text=Since%20the%20gravitational%20potential%20energy,of%20the%20gravitational%20potential%20energy.

[@Valdagast]

"All work and no play makes Dianna a dull girl" Energy is that property which remains conserved under time symmetry.

[@TheCimbrianBull]

13:51 "...energy is always conserved." _"The conservation of energy shall not be violated!"_ - Nick Lucid of the channel The Science Asylum

[@FlyingSavannahs]

Listen carefully, Dianna says "conserved" not "preserved." Understandably confusable, but not being rigorous at a symposium can get you in a pickle.

[@TheCimbrianBull]

@@FlyingSavannahs Oh, my bad. Thanks for calling attention to this. I shall correct it immediately!

[@megamanx466]

Also, I've heard this statement typically refers to chemical reactions, but not necessarily nuclear ones. I think the "potential" energy within the molecules is simply converted from matter to energy though... if I recall learning after high school. 😅

[@explorali5405]

Sixth ☹️😜 Love from INDIA 💞💞💯

[@user-jt6ej7vh2p]

No 6th

[@kubrakocyigit8870]

You're so cool and pretty. The video consept and your narration were amazing. I love ittt🤯❤‍🔥

[@smartass0124]

Does 😘 really exchange kinetic and chemical energy.

[@megamanx466]

Technically a bit of kinetic energy, but mostly chemical energy in the brain. A hug might do about the same. 🥰

[@TheaDragonSpirit]

It was at 24:20 that Physics Girl blunder the pen, after previous blundering delta X. Fortunately she did enough to complete her task.

[@dij8nz]

Thanks for another great lesson. I heard a term the other day and I was hoping you could explain it. I'm guessing it has a lot of potential (pun intended) relevance to the energy transfer you just talked about. The term was "static friction". What's the difference between static and non-static friction? Is that a whole lesson in itself?

[@thespartan5515]

google

[@savary62]

What about the change in the weight of the rocket due to the exhaust?

[@tegneren]

6:08 I see Simone didn't just help you with the bowling ball pendulum ;)

[@fakhermokadem11]

When we say say we exercise a force of 100N on the cow, does that mean a one-time instantaneous slap of 100N, or a continuous push of 100N for the length DeltaX ?

[@megamanx466]

I'm not 100% sure, but I believe that 100N is a 100N. The velocity doesn't otherwise matter, because the result is the same.

[@raykent3211]

A continuous push which, if not constant, averages 100N over dx. If the slap took zero time there would be no transfer of energy into the cow, only conversion of your muscular energy into heat.

[@megamanx466]

@@raykent3211 Lol...well a slap takes at least some time. If the slap was ACTUALLY 100N of force, then it might move part of a cow as the flesh absorbs the impact, but that's about it... because it's only around 22 lbs. of force. He did say "instantaneous" though, so I see why you'd say "zero time".

[@davewilson3951]

I love it when you talk nerdy 😇