Kepler's Three Laws Explained

Kepler's Three Law's were groundbreaking in that they accurately described the motion of the planets around the sun. They dispelled the idea that the orbits were not circular but elliptical.
However, it was not until Newton that we understood why Kepler's Laws work.
Kepler's work was not in a vacuum however, and was the culmination of hundreds of years of studying the stars - from Aristotle's and Ptolemy's geocentric model to Copernicus' geocentric model and the meticulous measurement of the planets by Tycho Brahe
This video provided an introduction to the scientific history and then proceeds to discuss Kepler's three laws
CHECK OUT THE LESSON ON KEPLER'S LAWS - WITH LOTS OF RESOURCES - www.physicshigh.com/kepler.html
A brief index if you wish to jump straight to the laws
0:00 start
0:43 Ptolemy
2:27 Copernicus
3:55 Tycho Brahe and Kepler
5:38 Kepler's 1st Law
7:15 Kepler's 2nd Law
9:15 Kepler's 3rd Law
12:13 Isaac Newton's explanation
15:25 an example
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[@ZhounaMusic]

When you went through 5 lectures and 3 discussions and still have no clue what the three laws are exactly, and a KZbin video can explain it clearly in less than 20 minutes. You really start questioning our country's education system...

[@PhysicsHigh]

Im glad I was able to hep you

[@shig8888]

I keep hearing different versions of this, the reason why you find KZbin videos simpler is most likely because you're simply paying more attention or because you have the ability to pause a video. If you have actually gone through 5 lectures and still didn't understand it, you might just be a dumbass.

[@-TheInfamousOne-]

The difference is people used to go and seek a great teacher, now children are provided one by the state that teachs a 3yo-3000yo curriculum.

[@Matteop113wo]

same boat here this video saved so much time and was great to watch

[@matthewfang440]

@@PhysicsHigh help* why can't you spell

[@reka6356]

i think my brain just melted out through my ears - I can't fathom how you guys' brains just work like this. I have a huge respect towards all scientists but especially the ones dealing with mathematics . It truly is a talent you have to be born with, to see numbers in such a complex way and understand immediately. It takes me a long time to GET IT. Thank you for this video, it did help a lot!!

[@algotraderoptionnfutures4885]

Imagine those times no schools, libraries, printing presses etc.. All these discoveries were interdependent.. how they had access to each others discoveries..who documented it?

[@zrATT_]

​@algotraderoptionnfutures4885 maybe they used WhatsApp back then

[@kwiky5643]

Trust me they are all extremely intelligent, more than me or you, but they work a lot too to become that good. There’s no miracle in science

[@kwiky5643]

@@algotraderoptionnfutures4885most sent letters to each other

[@Heiressesoftheking]

5:37 is when he starts talking about the three laws. You're welcome!

[@kedarhaldankar1316]

Thanks X

[@Heiressesoftheking]

@@kedarhaldankar1316 You're welcome!

[@samb9049]

t.y.

[@marczoorob7042]

Saved my life

[@guuguu7559]

My love

[@blazetech6614]

It took me all night to understand the 3rd Law. Thanks for relating Newton and Kepler's Concepts

[@cleyowki]

We will be reporting abt the 3rd law and now I'm starting to get scared just by seeing ur comment (knowing that I'm bad at physics) lmao

[@gudeliop]

same @@cleyowki

[@ivimarie1]

This is soo cool! I love the interactive way of learning. Thank you thank you! I have watched so many videos and only this one has really made sense to me.

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So accessible this video content……. we should preserve this

[@ranganathsh989]

very good explanation.

[@jcj-ik8lc]

Beautiful presentation ! Thank you.

[@jammy_pingu4434]

very well done compliments

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Love your profile pic 😂

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This was the video I was looking for.

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Wow, excellent video!

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Thank you so much, keep up the good work dude ❤

[@PhysicsHigh]

Thanks

[@cotyw090]

Well done!

[@cashchristian-im2lt]

thx for the video

[@Thundar]

thank you this helped a lot

[@pushpalatachoudhary3313]

Nice explanation

[@maddieryan6076]

this helped me a lot with my science essay, it helped me more clearly understand the three laws

[@lebohangthwala6347]

It really was short and brief.

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Me too Also subscribe to my channel

[@Ion_thruster]

@@untitiled1092 No I will definitly not

[@girlyo]

🔥🔥this is amazingggg🥺🥺

[@omarwahab9569]

really i am so grateful for you thanks !!!

[@user-xu6du4wi4g]

Thank you so much! I had to study Johannes Kepler for a school project and all other videos and websites were really confusing. You did such a good job explaining and simplifying Kepler's three laws. I would love to hear more from you!

[@PhysicsHigh]

Thanks. I have lots of videos on various topics and more to come.

[@matmurk8536]

Well done

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Awesome!!!

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Man that was really cool!

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Yes it really helped .. thank you ...

[@alanoodalmehri6714]

thanks sir,i really enjoyed the video

[@PhysicsHigh]

Glad to hear that

[@tanooparavind9450]

Wonderfully explained, Sir.

[@cleofeenloran2060]

Thank you ❤

[@sabarishks6089]

Thank you so much sir.

[@kaiserredgamer8943]

7:34 ah thats why slingshot maneuvers are in closest approach possible

[@saikatislam1221]

Excellent

[@OmarChida]

Great explanation

[@PhysicsHigh]

Glad you liked it

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Thanks a lot, it's very helpful.

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Great Job

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Blow?

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Nice video

[@SCPNLCTF]

Thank you

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thanks sir.

[@geizlercabayao4637]

Good day, Sir may I know what application did you use in this video? It would mean a lot if you respond. Thank you!

[@PhysicsHigh]

You’ll find all that info on my website.

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thank homie this helped with my assignment

[@PhysicsHigh]

Glad it helped

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Thank you so much....

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Good video

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Great video. I really enjoyed learning it. Thanks

[@sscaspirantwalatrader]

Thankksss

[@lovenoeli]

time stamp for Laws Of Planetary Motion: 7:03

[@sunithavinod1658]

Thanks mate!

[@untitiled1092]

I know right? Why did he do such a long intro

[@lucanwolfrl8044]

@@untitiled1092 well, I needed it sooo i can say that it's fine since you don't know who'll be watching this video. Some might find history useful and for some might not.

[@drewayrit7334]

Very helpful. Thanks.

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[@MatsumotoKael13]

absolute legend. thanks a bunch mate

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I love your video.

[@SuperExponential]

Wow...I didn't know that Uranus has a period of 30,589 days...that is such a long time for it's neighbors to put up with I think.

[@sherzadaritrizaman6949]

Most clear explanation!

[@geoffphillips8183]

Beautifully & delightfully explained. Thanks so much!!

[@mashaqureshi1535]

Very well explained

[@natashaayumie6748]

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[@anuradhachauhan2464]

Thank you sir it was really helpful

[@amarfakhredine591]

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[@PhysicsHigh]

Thanks

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Very nicely explained

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Thank you for this, it helped allot with multiple research papers. Keep it up!

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very good explanation skill

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I am so glad that I am enrolled in a college physics course that will only ever be of use to me in Kerbal Space Program

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Thank you. Very interesting.

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this helped me so much with school thank you so much

[@BobtheScienceGuy]

Would you allow me to mirror this on my channel? I'm looking for some solid basic science instruction for my viewers.

[@SpeedyNS_]

Dang, such an amazing video. Explained everything very well

[@rosshealea]

awesome! I refer to this video often in my college astronomy class.

[@yuandadong5177]

Great explanations. You are much better than my classroom teacher. But I suppose Kepler's law of period r^3/t^2=GM/4^2 would only work when the object revolving around a central mass in a circular motion. However, from the video, the eccentricity of mercury is 0.206, which should be large enough for its motion to be considered as elliptical. So my question is can you actually derive a equation that describe such an elliptical motion.

[@PhysicsHigh]

Kepler's third law is actually based on the semi major axis (aka r is the length of the semi major axis) so it applies to mercury was well

[@yuandadong5177]

To derive what R^3/T^2 equal to, you applied v= 2pi/r which is a formula for circle, and you applied the formula for uniform circular motion F= mv^2/r. Well, then the left hand side of Kepler's third law is for an ellipse, but the right hand side is derived using properties of circles. At least to me, it should not work with ellipse.

[@Gordian1095]

Skipped over some of the explanation of the formulas in 3rd law proofing. If you are going to explain it, please do it completely, step by step, without holes. Thanks.

[@BikramSarkaronline]

Good video. I am the first viewer, from India.

[@krishoberoi]

@@pedrovillalobos1995 WHAT??

[@realcygnus]

A gem of a channel !

[@PhysicsHigh]

Thanks for that.

[@user-yb2ic1ns7g]

When can I use R for radius and r for radius, or can it be used whenever I want?

[@PhysicsHigh]

We usually use a lowercase ‘r’.

[@kaiserredgamer8943]

If Apoapsis-Periapsis = 0, then Eccentricity = 0.

[@jakekluss620]

Blesssssssssss

[@untitiled1092]

How stupid do have to be.... EVERYONE knows that god is not real

[@JAMB685]

What software and hardware do you use to make your videos?

[@PhysicsHigh]

See my website under FAQ where I go through the equipment I use.

[@jackehlert655]

How does Kepler’s third law apply to elliptical orbits if it was derived from equations of uniform circular motion?

[@PhysicsHigh]

Actually Kleplers‘s law is derived on ellipses where “r” is the semi major axis. A circle is simply and an ellipse where the semimajor axis and the semi minor axis are the same size.

[@che7655]

On Keplers third law with the radius, how do you measure radius of an ellipse since it's constantly changing? Do you take the average radius across a single revolution or does it not matter and can you just take the radius at any point in the ellipse?

[@randoshmuckarias1296]

I believe its indeed the average

[@friendlyneighbourhoodai]

It's the mean/average distance from the Sun i.e. radius.

[@lightuponlight5215]

Respect for Ptolemy

[@albusdooley8252]

how did kepler's laws of planetary motion change some of the ideas in the ptolemaic and copernican theories?

[@PhysicsHigh]

This needs a longer response but in essence Ptolemaic model was geocentric the others heliocentric. Copernican model was circular where as Kepler demonstrated it was elliptical.

[@albusdooley8252]

@@PhysicsHigh Thank you very much, now I got my answer for my homework💕

[@littlesniperop7600]

how dose it go the same speed if it is far away didn't he just say it was slower when its far away by the way I am talking about the 1st law

[@craffte]

Of course nobody answers...

[@PhysicsHigh]

Not sure what you are asking. A object in an elliptical orbit will have a variable speed, faster when it’s closer. Kepler describes this but could explain it. It took Newton to explain with Gravitation

[@mrvannunen4987]

Question: What software do you use to produce these videos?

[@PhysicsHigh]

I use Inspire from Promethian

[@hastakmerai5079]

How this r for every planet came from bcz the path is eliptical so r is not constant. So how it came from?

[@sastrykganti681]

Very well explained, BUT it would have given me more knowlege with no sacrifice to you if you had moved the earth in ONLY the correct direction but not back and forth! every little bit from you adds to my knowledge.

[@nick-qn5uy]

wait.. does F= m.V^2 / R comes from the centripetal acceleration multiplied by the mass. but the centripetal forces only imply for an object that is orbiting CIRCULARLY in which explained on the FIRST KEPPLER'S law, planets orbit in an oval shape. shouldnt the equation be un usable if this was the case. Thankyou

[@PhysicsHigh]

You are right in that the orbits are elliptical. But they are very close to circular. Thus means that the centripetal formula is s good approximation although in theory needs to take account of the elliptical path.

[@nick-qn5uy]

Thankyou very much

[@abbynormal1945]

What's fascinating about Kepler is that his belief in a God that created a perfect and ordered universe is what spurred him on to create a more accurate model for revolutions. The math is quite something!

[@charlesgodswill6161]

Does the elliptic orbit nature here corroborates the fact that the earth is not exactly spherical as it appears ??

[@aj_beyond]

It's really educating. thanks to you 🙏🙏

[@physicswitharsema8670]

Hi it nice video I have question for you What is ellipse ? in first law of Keplers

[@sascharurik527]

Magnificently said indeed.

[@PhysicsHigh]

thankyou

[@karthikasokan5741]

buddy thank you for this amazing video but you are wrong. K=T^2/R^3 and not the reciprocal

[@planetclownfishbrain7052]

This is just misdirection to prevent you from discovering the simulation sequence.Hint: Look for the subtle glitches.

[@cashchristian-im2lt]

my brain hurts from watching this.

[@robertduncan4612]

Please explain/illustrate how/why the moon is tidally locked showing Earth only about 59% of its surface.

[@planetclownfishbrain7052]

Spoiler: The moon is flat too.

[@Ghostbuster07]

Isn’t it because of how the moon rotates as it revolves around the earth? Synchronous rotation? Where it takes just as long to rotate about its axis, as it does to make one revolution. I’m not sure why it’s like that though. I would assume it’s because of gravity. I’m sure billions of years ago it wasn’t like how it is now

[@fitriiskandar3572]

is that the explaination why the sun always goes big and small all the time?

[@jankijoshi5152]

I am unable to understand keplers 3rd law Dont know why??? Its very tuffffffff😥

[@kainpepsi3731]

Is Kepler’s first, second, and third law of planetary motion is true? EXPLAIN.

[@PhysicsHigh]

Yes. Why would you ask? Keplers laws describe the motion of planets and the amount of data we have on planet positions is overwhelming that can easily verify keplers laws.

[@cheapmonks]

Is "Planetary Law of Motion" same as "Law of Planetary Motion"? Just asking.

[@rushilgupta7987]

How can you measure the radius in elipses? wouldn't the radius change in different positions of the planet.

[@PhysicsHigh]

Good question The actual Keller’s law refers to the half the semi major axis. With a circle it’s the radius with an ellipse it’s half the greater diameter. Since most orbits of planets have an eccentricity of very close to 1, the radius is fine to use.

[@rushilgupta7987]

@@PhysicsHigh alright I get it, thanks a lot dude,

[@jamestorreano3299]

When and how did the idea of "squaring" become so important in math?

[@PhysicsHigh]

Look up Emilie Du Châtelet

[@bschoolofai]

13:45 Why is the velocity taken for a circular motion while it isn't circular but elliptical ?

[@PhysicsHigh]

True, but the case of high school circle a good approximation.

[@ojas3464]

👍

[@DSCS_HarshaS]

Can someone explain why is R^3/T^2 the same for all the planets even though each planet has a different G?

[@PhysicsHigh]

G is a constant value independent of the mass of any planet

[@DSCS_HarshaS]

@@PhysicsHigh but sir www.quora.com/Does-the-gravitational-constant-having-the-same-value-around-the-universe-mean-that-the-gravitational-fields-of-all-planets-etc-are-the-same#:~:text=No%2C%20the%20gravitational%20constant%20being,is%20not%20like%20the%20Earth.

[@PhysicsHigh]

They're saying what I am saying . You are mixing up up G , the gravitational constant, with 'g', the gravitational field strength. And Kepler's Law is about the G , the gravitational constant

[@DSCS_HarshaS]

@@PhysicsHigh Thank you sir my doubt is cleared

[@koi_leee]

how do you do powerpoint presenataions like that? the one that allows the earth move