Gravity and Orbital Mechanics - Physics 101 / AP Physics 1 Review with Dianna Cowern

Рет қаралды 165,372

Күн бұрын

Lesson 8 (Gravitation and Orbits) of Dianna's Intro Physics Class on Physics Girl. Never taken physics before? Want to learn the basics of physics? Need an AP Physics 1 review before the exam? This course is for you!
Exercises in this video:
1. An object with mass M is a distance R from the center of the earth. Another object with mass 2M is at a distance 3R from the center of the earth. What is the ratio of the forces between each object and the earth?
2. What is the force of gravity between the Earth and a pineapple with mass of 1kg, if the pineapple is falling near the Earth’s surface?
3. What would the acceleration due to gravity be on a planet with half the radius, but twice the mass of Earth?
4. The ISS orbits with an average altitude of 410 km. What is its orbital velocity? What is its orbital period?
5. Extras Credit: What is the orbital velocity of an object orbiting the Earth at a height of 35,800 km above the Earth’s equator? (Don’t forget to add in the Earth’s radius!). What is the orbital period?
Credits:
Dianna Cowern - Executive Producer/Host/Writer
Jeff Brock - Lead Writer/Course Designer
Laura Chernikoff - Producer
Victoria C. Page - Video Editor
Sophia Chen - Researcher/Writer
Erika K. Carlson - Researcher/Writer
Hope Butner - Production Assistant
Levi Butner - Videographer
Lauren Ivy - Set Design
Vanessa Hill - Consulting Producer
Aleeza McCant - Illustrator
Rachel Allen - Illustrator
Consultant - Kyle Kitzmiller
Lucy Brock, Samantha Ward - Curriculum Consultants
Cathy Cowern - Transcription

Пікірлер: 553

@ianmckinnon4325 3 жыл бұрын

In 1969, when I was 12, my parents gave me a book about Isaac Newton. I was immediately hooked on science. Watching this video I finally “got” it, even affter graduating from University with a degree in engineering. Thanks Diana!

@mjones207 3 жыл бұрын

11:01 "...Fall around Earth and keep missing." That's how Arthur Dent learned how to fly... he threw himself at the ground, but missed.

@robertcrites9250 3 жыл бұрын

Excellent !!!

@astrophiledevansh898 3 жыл бұрын

Genius

@astrophiledevansh898 3 жыл бұрын

He was in orbit

@Paul_Ch52 3 жыл бұрын

Arthur was born in England well after Newton. Of course he would have learned the equations. Why wouldn't he fly? I, myself, have tried this but keep forgetting the miss part.

@CellRus 3 жыл бұрын

I love it. Learning about gravity was my favourite thing in high school. I just find astrophysics absolutely incredible. Like to imagine measuring the mass of a star without using a weight is just simply astonishing. I love these lessons.

@PeterBeckleyArt 3 жыл бұрын

"The masses cancel out or every time an astronaut stepped out of the ISS there'd be a problem" was a wonderful revelation for me. I inherently knew that it didn't affect the orbit radius or velocity, but seeing the math in this episode is what actual lit the bulb above my head. Thanks! Do you know of any experiments where we can see lasers being affected by gravity?

@paramaguru2007 3 жыл бұрын

At small scale, (few meters) The lights bends to a size of a proton! Not enough for observation. I doubt we have an experiment for that. Even LHC needs gravational wave distortions to identify it. But at very large scale it happens! Gravitational lensing!!!

@212caboose 3 жыл бұрын

How can anyone dislike how enthusiastic Dianna is about physics? I mean c'mon!! It's seriously contagious!

@IceBergGeo 3 жыл бұрын

I love that you still make mistakes, even though you edit them to make it correct. Just shows that anybody can make them, and we need to double check what we do before we submit our work.

@dennislu8790 3 жыл бұрын

When Diana uploads, I click fast. :D

@SpiderSla7er 3 жыл бұрын

If only teachers taught me this interesting I would not sleep during my physics class

@CoolAcid 3 жыл бұрын

That π² was freaking me out. I thought I was still asleep, lol.

@pierfrancescopeperoni 3 жыл бұрын

π² is six times the sum of the reciprocal of the squares: (1+1/4+1/9+ 1/16+1/25+1/36+...)*6=π²

@cjmenagh882 3 жыл бұрын

Having recently rewatched Feynman’s lectures on beginning physics I am very pleased to let you know I think yours are obviously more fun but also better, more easily understood, and engaging to the point that we can agree that physics is phun to learn or even re- learn. Thanks for doing these.

@Omnifarious0 3 жыл бұрын

I love the way you teach these. Very accessible, and your enthusiasm is infectious.

@DyslexicMitochondria 3 жыл бұрын

This series is soooo educational, informative and entertaining. I am thinking about doing something like this too. Keep up the amazing work!

@epicstuff7522 3 жыл бұрын

ikr

@AppNasty 3 жыл бұрын

Amazing how each equation connected to the next. Math is truly the universal language of the universe.

@roytee3127 3 жыл бұрын

This is the most awesome video I've seen in a long time. She brings together so many concepts, with an obvious enthusiasm. I love it that she starts with the historical problem. And does the math (including cancelling out units - the magic trick of physics!) And I'm gobsmacked by the video of a candle burning in freefall - brilliant! I wish they had spent more time on that. Because it illustrates the equivalence principle of general relativity so well - if you know that flames act the same way on the ISS. (And the slinky thing is mind-boggling, too.)

@petelynch9468 3 жыл бұрын

Einstein's equivalence (20:25) that inertial mass and gravitational mass are the same. When you accelerate an object that acceleration acts on all parts of the object to the same extent. However when an object is in a gravitational field the effect differs due to some parts of the object being closer to the centre of gravity than other parts. So this equivalence only works for points, not for real-life objects with finite dimensions. In theory, at least, it should be possible to detect this change in gravitational attraction across the size of an object. While the effect will be very, very, small it would still exist.

@StatsScott 3 жыл бұрын

What a great informative video! I’ve listened to several physics/astronomy courses and this was the first lecture that made orbits make sense. Will have to show my kids as I think they will enjoy it as well.

@pawesomeadventuresmaine882 3 жыл бұрын

Between 2000 and 2002 I did my masters research at NASA Glenn on the vomit comit. It would fly up to Cleveland for a week for us to fly on. My reasearch was zero gravity combustion of pure carbon in an oxygen enriched atmosphere. I got to see spherical flames in person more times than I care to remember. I was one of the lucky few who got to fly in the KC-135 numerous times and fly hundreds of parabolas!

@bobjackson6669 Жыл бұрын

Brilliant lecture that I was able to share with my grandchildren. Thank you for the excellent lecture. Two thumbs Up!

@llaauuddrruupp 3 жыл бұрын

I say it every time: I love these 'class' videos so much! :-)

@chrismarcus2751 3 жыл бұрын

You are an amazing teacher. I am taking AP Physics 1 and your videos are of great help.

@evelynbrylow3624 3 жыл бұрын

3:21 “holy Europa!” lol!!! Love that, especially since Jupiter has a moon called Europa

@spacebarbarian._ 3 жыл бұрын

Its one of the four biggest moons, called Galilean moons

@Paul_Ch52 3 жыл бұрын

I think that's why she said it. She knew that. She's a sharp one. Her humor with that intellectual base to it.

@MAULIKPATELnamste 3 жыл бұрын

@physics_Girl, you are amazing at explaining stuff!! Thank you.

@kirbpernicus9689 3 жыл бұрын

This channel is always delivering amazing content like this, great work!

@sahildhaked7839 3 жыл бұрын

chutiya

@andrewfrank7222 3 жыл бұрын

The crazy part about General Relativity is not that Newton's model is wrong, it's that you have to throw out your intuition about what you are observing when the apple "falls" to the ground... The apple isn't being pulled to the ground. My hand is accelerating away from the apple and the ground is accelerating up to meet the apple... Sounds like BS, but is in fact what is happening. 4D movement is so mind blowing...

@Wayne70 2 жыл бұрын

Wow your mind is amazing, you manage to explain things in such an easy to understand format.

@13loodySword 3 жыл бұрын

"an even heavier apple" when lifting up the PINEapple lol

@neoanderson7 3 жыл бұрын

Indeed, these episodes are great. Helps the beginner as well as some seasoned people. 😉👏🏻👍🏻

@shriyaramasimha2354 3 жыл бұрын

Awesome! When Gravity pulls us down to the Earth while we jump, it's the best example that anyone on EARTH could understand :)

@JerehmiaBoaz 3 жыл бұрын

Except that Einstein's equivalence principle tells us this perception is wrong and instead of us accelerating down towards Earth when we're falling it's actually Earth accelerating up towards us (just like the floor of an accelerating spaceship you're on is accelerating up towards you).

@davetarrant6888 2 жыл бұрын

@@JerehmiaBoaz I have seen and heard that explanation. What I can not wrap my head around is this. If earth is accelerating toward me when I jump up, then how can it be for someone that would be on the opposite side of the planet and jumped up at the same time I did then how could earth accelerate in two different directions at the same time?

@engineer1able 2 жыл бұрын

@@davetarrant6888 Thats where curvature of spacetime comes in; what looks to be two different directions in non-curved space is actually the same direction in curved space.

@leowright9554 3 жыл бұрын

8 minutes, yes, 8 minutes and I already learned what I didn't learn at high school. I wish every teacher would teach as you do :( Cheers and respect from Mexico!

@furn2313 3 жыл бұрын

These are honestly golden I don't know why they aren't getting views

@samedwards6683 5 ай бұрын

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 🙏

@Arestkaramazov 3 жыл бұрын

This video is really nice, physics and math together, great job! Hello from DR

@-_IT_- 3 жыл бұрын

You deserver your own TV show! Educational and entertaining, the type of shows I grew up watching, Bill Nye, Mr. Wizard's World, Beckman's World to name a few.

@matthewsaulsbury3011 3 жыл бұрын

Wow, this is very neat and fascinating! 👍🏻😀 Keep up the good work!

@jegeg2922 3 жыл бұрын

Wow this channel is what I have been looking for

@SH4TL32 3 жыл бұрын

Where have you been all my life! Thank you for this, you're awesome ! Xox

@mrjoshmtz97 3 жыл бұрын

I enjoy watching this series!

@EngChagas 2 жыл бұрын

What an excellent video. Thanks and congratulations.

@hariyantosyamsudin2456 3 жыл бұрын

I love physics, with Dianna Cowern its just perfect to watch! Cant wait to see your pretty face collaboration with others physics Master, Neil de Grass? Michio kaku? Just too excited!

@sharondavis3535 4 ай бұрын

I pray your health improves exponentially ❤ just discovered your amazing work.

@user-sc5dy6ur2h 3 жыл бұрын

Some questions : What would happen if we drop another earth, on earth?Would the solar system be distributed and hence the universe? If we will move something in the universe such that it's trajectory is changed,would it effect the universe, the grav field all around? Radius of the earth is variable , then what is 6400km? How do we calculate the mass of the earth?

@DFPercush 3 жыл бұрын

If the mass of Earth suddenly doubled one day, I don't think the other planets would notice too much, there would be a small affect, maybe to asteroids, but we'd stay in our orbit around the sun. The moon however, would take on an eccentric orbit around the Earth, making tides vary in strength at different times of the month. I'm not sure what you mean by distributed, though. Technically every atom has a gravitational influence that extends across the entire universe, so even the orbits of distant planets send out gravitational waves, it's just too faint and the wavelength is too long to ever notice. So, yes, but not in any real significant way. Usually when people quote the radius of Earth they mean the equatorial radius, but it never hurts to make a distinction. Considering that we can bounce lasers off the moon and measure its distance directly, you could use the same trick that Diana used to "weigh the sun" on the earth/moon system. We know r by direct measurement, and the period by the lunar cycle (time between full moons). I'm sure there are other ways to get the mass of Earth just a search away as well. ;)

@akshinbarathi8914 3 жыл бұрын

@@DFPercush THE mass of earth is not that great when compares that to the distances betwenn planets is too huge infact u urself can fit 30 earths in between earth and mooon so if earth and another earth collide it would cause a lot of debris and the debrois may revolve around the moon and the moon trajectory may change

@DFPercush 3 жыл бұрын

@@akshinbarathi8914 I'm just assuming we could magically double the mass of Earth without affecting its own trajectory. But yes, if an actual rogue planet or something collided with Earth it would mess with all kind of things, it just depends on the relative speed and direction, where the moon was in relation at the time, lots of factors.

@DougPowell01 3 жыл бұрын

A fun way to visualize the laser beam while in motion idea is to substitute a tennis ball. As kids, two of us would climb on to opposite sides of a merry go round, spin it up, and play catch with the ball. Try it out, it's pretty fun.

@garbajeur3585 3 жыл бұрын

It’s not even 6am yet and I’ve learned so much! Thanks you!

@alecthesceptic6373 3 жыл бұрын

You are a great teacher and communicator D. Great video.

@charles_wipman 3 жыл бұрын

Usualy when i think on gravity i use to think in how the planes maniouver in relation to each other and how this affect their missiles and cannon rounds, also how the gravity affect the rounds of a rifle when you aim down or up and how this affect the range and point of impact; it's great to learn how the universe really work.

@lucace1090 3 жыл бұрын

i thought the title of the thumbnail is “i ♥ gravity“ i have bamboozled yet again...

@naveenraj2008eee 3 жыл бұрын

Mind blowing lesson diana.. Thanks. Awaiting for more physics lesson..

@evil_zebra4275 3 жыл бұрын

Omggggggg this like the earliest I have ever been to ANYTHING

@Paul_Ch52 3 жыл бұрын

Impressive, Dianna. We see you enticing your target audience into the fields of science. Thank you for inspiring our young. I sure hope it works.

@mrslothman03 3 жыл бұрын

Thank you! This was great!

@drstronk 3 жыл бұрын

amazing video!! thx for the informations u r giving to us

@deepakjoshi823 3 жыл бұрын

Thank you Ms. Dianna!❤🤗

@pedrobluis 3 жыл бұрын

One hundred thousand million stars? Loved it! One billion should indeed be million millions.

@kirkelicious 3 жыл бұрын

Well, for now you have to accept that one billion is one thousand millions. Changing that would make things really confusing.

@iampuzzleman282 3 жыл бұрын

No cross outs , magic marker use is perfect. Awesome

@itsreeah2663 3 жыл бұрын

Oh my gosh physics girl I love you and your content. Please make more physics content because of you I am really enjoying science not that I didn’t already but I just love it even more thank you from the UK 🇬🇧❤️

@alejandroartolachipigranad700 3 жыл бұрын

Omg this is great I love it!! You're the best!! ❤❤ Do you teach classes?? Where!?? Anyway, it's really good but I think it would have been better if you explained where those equations came from, as in guiding us to come up with those equations ourselves, to understand it better. Anyway keep it up!

@user-ch2ef5ez3c 3 жыл бұрын

it's so cute to regard gavitation WITH OUT LIGHTS FROM & TO BOUTH OF THE STARS!!!

@Nyfgheist52528 3 жыл бұрын

I didn't have the chance to get a scientific background, this is really helpful to me who's just curious, I'm subscribing.

@dennismcavoy860 3 жыл бұрын

Dianna that is impressive so are you great video thanks.

@ScottKentEdu 3 жыл бұрын

The comparison between the laser in a space ship and bending into the gravitational field finally made that connection click. Wow.

@aadhya8459 3 жыл бұрын

Hey, Dianna! I was actually very late to start watching this series, and so I decided to watch them all in just eight days, watching one in a day, but when they got done and I was waiting for this one, KZfaq had suddenly started to bore me... You are like one of my crazy friends, but the problem is that I am unable to understand Einstein's theory of relativity... Edit: And yes! Thanks for teaching us a lot in return for nothing, you actually did what no one on KZfaq could ever do: make me understand 2D MOTION, FRICTION, CIRCULAR MOTION, etc.

@amsyardanialz4080 3 жыл бұрын

Amazing series

@hotflashfoto 9 ай бұрын

At 1:08, "... an even heavier apple ..." Your humor is just so funny! I hope to see you back on The Tube soon. We all miss you and want the best for you.

@almosh3271 3 жыл бұрын

Diana Now this was a good lesson. Job well done and bravo. Keep up the good work. :)

@sophierivas5682 3 жыл бұрын

You are the best you are even on KZfaq Kids!!!!!!!!!!!!!!!!!!!

@Roberto-REME 2 жыл бұрын

Outstanding video Dianna. Your explanations a cogent, interesting and your narration is superb. And, ....you're gorgeous.

@damaliamarsi2006 3 жыл бұрын

I'm in love. Physics rocks!

@charlesbromberick4247 2 жыл бұрын

Really well done! (When I started this video I wondered if you would treat the case of geostationary orbits - like for communication satelites, etc.)

@Zonks666 3 жыл бұрын

Question to get lost in the ether: How much mass would we have to bring from other planets/moons to Earth to significantly mess up orbit/tides? eg mining on the moon without swapping mass out

@Shenron557 3 жыл бұрын

Mining the moon for current human needs (and with currently available mining technology), won't make any significant change to the mass of the moon and therefore, tides on the earth. For example, if the current annual iron ore mining is at 130 million tones per year (1.3 x 10^11 kg/year), it would take a little more than half a billion years to reduce the moon's mass by 0.1%. Assuming humans (or human descendants) survive for half a billion years, they would probably be mining quasars for energy 🤣 (or something else that's totally out of today's speculation/human knowledge).

@Zonks666 3 жыл бұрын

@@Shenron557 cant believe I didnt think of it like that. Strange to wrap your head around numbers and masses that big when you arent a numbers person

@DFPercush 3 жыл бұрын

If the mass of Earth suddenly increased by a significant amount somehow, like a collision with another planet, it would give the moon an eccentric orbit, so the tides would be much stronger or weaker at different times of the month. If the mass was added slowly over many years, it would increase the orbital velocity of the moon and make the lunar cycle shorter. It might pull it a little bit closer but I haven't mathed that out. In which case tides would be stronger. But again, the numbers that humans could realistically achieve in the foreseeable future is completely insignificant.

@PapaFlammy69 3 жыл бұрын

Nice.

@khaledhasan8495 3 жыл бұрын

I thought you were mocking physicests

@saadhassan8813 3 жыл бұрын

This is just amazing

@davecarsley8773 2 жыл бұрын

3:43 Yes, there's definitely an attraction between us, Physics Girl. I'm so glad you've finally realized it too. ;-)

@hbsanchez9733 3 жыл бұрын

This is awesome!!!

@MichaelDuarte 3 жыл бұрын

I loved this video. Thank you

@patk1013 3 жыл бұрын

I loved it, ty so much

@Sci_Academy 3 жыл бұрын

This video is educational with nicely explained

@Delostacia 3 жыл бұрын

Love you so much.... thank you.

@timeverse1545 3 жыл бұрын

U are amazing !! And ur videos are amazing !

@Maria_44426 3 жыл бұрын

Wow I’m Learning physics and I’m nine years old and my brother watches you

@nathangoddard8115 3 жыл бұрын

Love the video. I wish we would start referring to the maximum speed in the universe as the speed of causality or speed of information.

@thomasewing2656 2 жыл бұрын

The 'speed of thought'.

@More-Space-In-Ear 3 жыл бұрын

My head hurts but, it’s eased by the smile from Dianna 😉😊

@mohammedal-haddad2652 3 жыл бұрын

I always wondered how we measured the mass of the sun. Thank you very much.

@deanambrose9475 3 жыл бұрын

Soooooo clever. love it learned so mutch

@neallasta 3 жыл бұрын

just in time. Thanks!

@harrisonbarber5070 3 жыл бұрын

Physics girl has been watching veritasium recently... the tangent at the en (about relativity) is a tell

@davidkatuin4527 2 жыл бұрын

Explaining what someone else has explained and still not understanding what gravity is. Lol, love it! Thanks for the vid

@mouthmuzik 3 жыл бұрын

Why are you so awesome....??? GREAT video!!

@jorrvaskr9963 3 жыл бұрын

Love the Starset mask!

@pasha12343 3 жыл бұрын

Nicely explained, 👍🙂

@vishalsinghrathore9989 3 жыл бұрын

Love this

@markedis5902 3 жыл бұрын

Dark matter is simply matter in a different dimension. We are only conscious in 3 dimensions but there are many others. This also explains a large amount of quantum theory. For example quantum entanglement. The particles can be far apart in the 3 conscious dimensions (x,y, & z) but they haven’t moved in another dimension (for example ‘q’)

@raphner2759 3 жыл бұрын

I love this series and it taught me a lot, but I think you should have explained the gravity formula

@doctorsahib8466 3 жыл бұрын

excellent thank you very much 💓💓💓💓💓

@kevindelahoussaye3808 3 жыл бұрын

I really enjoyed the Apple-Pineapple part!

@richardsauceda7074 3 жыл бұрын

Nice catch !!!👍😎

@RockyTremblay 3 жыл бұрын

Diana, You are too good to be true-almost. Thank you.

@Suzz2210 3 жыл бұрын

Amazing 👍

@tonyhammond4539 3 жыл бұрын

awesome almost got what you are describing but almost just about but not quite

@peterihre9373 3 жыл бұрын

You are amazing!

@CraigConnors 3 жыл бұрын

Hey Dianna - Does any object moving on Earth create it's own minute gravitational wave since it is moving within the Earths gravity and disrupting the normal flow of gravity?