Heat and Temperature

We all know what it's like to feel hot or cold. But what is hot? What is cold? What is heat? What does temperature really measure? Don't pretend like you haven't lost sleep over this. Well you don't have to fret any longer, Prof Dave will take you through the details.
Watch the whole Classical Physics playlist: bit.ly/ProfDavePhysics1
Modern Physics Tutorials: bit.ly/ProfDavePhysics2
Mathematics Tutorials: bit.ly/ProfDaveMaths
General Chemistry Tutorials: bit.ly/ProfDaveGenChem
Organic Chemistry Tutorials: bit.ly/ProfDaveOrgChem
Biochemistry Tutorials: bit.ly/ProfDaveBiochem
Biology Tutorials: bit.ly/ProfDaveBio
EMAIL► [e-mail]
PATREON► / professordaveexplains
Check out "Is This Wi-Fi Organic?", my book on disarming pseudoscience!
Amazon: amzn.to/2HtNpVH
Bookshop: bit.ly/39cKADM
Barnes and Noble: bit.ly/3pUjmrn
Book Depository: bit.ly/3aOVDlT

[@professor_m_gibbons]

@3:03 - the transfer of heat energy will NOT always alter the temperature of a system, such as when a phase change is occurring at a constant pressure. Very common misconception, so watch out.

[@ProfessorDaveExplains]

Yes good point, that was a misspeak on my part.

[@professor_m_gibbons]

@@ProfessorDaveExplains It's true 99% of the time we're talking about solid objects though, so I understand. Thanks for the reply!

[@10anjalinarayan60]

@@ProfessorDaveExplains u can pin her comment

[@localverse]

@@professor_m_gibbons Does that mean the heat's energy temporarily stops going into kinetic energy and instead goes into breaking bonds at the instance of phase change (with constant pressure) then switches back to affecting kinetic speed of molecules after the phase change?

[@smaran353]

One question: Isn't the expression "heat flows from" misleading and incorrect? Instead, the expressions "thermal energy flows from" or "heat flow occurs from" are actually correct, isn't it?

[@morrainn815]

man,,, this dude really be saving my grades. thank you professor jesus

[@samyukta4746]

jesus😂😂

[@kingboi7856]

jesus LOL

[@leagodalle995]

yooo look at the top of his head!

[@dalemalunes1100]

Wtf QHAHAHAB

[@AnthaxPhotoworks]

Hello

[@alias40anon]

Excellent short and simple explanation.

[@pritchardsangai3288]

I love the explanations, thank you very much.

[@kedarparab8001]

Man you actually explained nicely and scientifically than other videos

[@aedenthegreatyt]

My Chem. Honors teacher had me watch this video for an assignment. I was not disappointed.

[@aedenthegreatyt]

Any hard science concept: *exists* Dave: *Understandable, have a great day*

[@vivianasierra1]

thank you I needed this video for my end of the year test!!! :)

[@jorostuff]

I love when he says: "Let's check comprehension." I LOVE IT!

[@Jen-gl1hn]

Ikr!! Like it helps me a LOT

[@ShyaMKumAr-bo1ji]

*GREAT EXPLANATION* 🙏

[@retsepilemothepu1396]

My Physics improved from 50% on semester test 1 to 97% on semester test 2🎉🎉 Thank you sir, I have nothing to offer. I’ll thank you properly in the future.

[@SW-nx4jz]

Omg your the best! Thermochemistry is so confusing to me but your making it alot easier. I can't say thank you enough for these quick video!

[@paramitam4002]

teen Titans go Can we feel temperature kzbin.info/www/bejne/qXzLlJSiZqaVf8k

[@joserobing661]

Thanks for your clarity of ideas and simple presentation

[@chrispieG]

Professor Dave. You're the man!!! My Gr. 10 class finally gets it.

[@voltdragneel1052]

after 10 hours I have my chemistry test and I was reading thermodynamic when I see notification of your video lol and yhea you're videos are useful

[@ProfessorDaveExplains]

more thermo all next week!

[@prisminc158]

Is that Kaneki/Haise?

[@controlequebrado4455]

your*

[@xyrhdks]

i didn’t understand one single thing lmao, i guess i’m really dumb

[@katrinamae3510]

The song at the checking comprehension is so calming lol

[@raedibrahim9409]

I love your lectures 😍

[@carolarentz3208]

Thanks so much for the video it helped A LOT!!!! :)

[@kevinlapulapu8651]

thankful for your lecture

[@niceguy4801]

Thankyou professor dave!

[@user-fi8pi3eo5s]

Great explanation!

[@howitzerm777]

i just saw the intro and was instant subscribe push!

[@crazygamers9574]

तुला जास्त येतय का वेड्या

[@po4187]

wtf his intro is cringe asf

[@geramaerosales572]

Great Video! very useful as a resource material

[@mohammadhafeezullah1846]

thanks for my completing the first question of my assignment

[@binabonmary.marbaniang6456]

Love the explanation👍👍👍

[@hindutva2685]

Outstanding explaination sir

[@hari8654]

Thanks you sir most conceptual video

[@oliverbrunncarstens4215]

Thank you Dave!

[@nirupamam2814]

All of your videos are very very very very nice....

[@binadam9459]

I love you man, you are brilliant

[@fooliery6216]

I ended up here after watching the first 4 videos in the "Math and Science" channel -chemistry 1. It become paid to see at the same point where Prof. Dave here pics up the topic. Thanks for not making me Pay to Learn Dave. I wanna learn for free

[@danielcastagna1941]

Thank you so much Dave Grohl \m/

[@carolarentz3208]

YOU SHOULD BE MY TEACHER!!!!!!!!

[@subhashishbehera2424]

Sir you're explaining things really good

[@ahappyimago]

U da man, dave!!

[@lowall]

i like very to the point and easy to understand :D

[@Jihad_Sakib]

Man, your are so amazing 💗 , thank you 😊

[@richardfraussen1057]

Wish I had professor Dave videos during my studies, 55 years ago.

[@mahmoudhalawa5588]

Thanks so much ❤️😊

[@subikshayakumar9779]

Thank you sir

[@abutaymiyyahlectures]

this lecture was mind blowing ngl

[@robertolara3820]

great man!!!! thanks!!!!

[@ghost0_01]

Wow thank you so much!

[@brianfrancis5548]

"all phases of matter expand with higher temperature" actually not always true. the density of water decreases as the temperature increases from 32F to 39F

[@tokahuissen6615]

it is really good

[@rekhadevi9672]

Helpful..!

[@Ethan-uo6fv]

2:22 Not all phases of matter expand with higher temperature. Water for example, is at its densest at 3.98 ⁰ C (according to the internet). Contraction upon heating in solids is called "negative thermal expansion."

[@SamiUllah-bg2br]

You have no indeed explained it very well sir

[@user-dg6lo9fn8u]

Thank you sir!

[@cbtaylor303]

I have a question that has troubled me for some time (making the link between the atomic world to the macroscopic). What happens if we have a spaceship in outer space, and let’s say it’s a perfect vacuum (so no friction will occur). If we accelerate the spaceship, it now has higher velocity and so higher kinetic energy. You could say therefore it has higher temperature? After all the average kinetic energy of all the particles has increased? This doesn’t make sense though. Is temperature relative? Another similar problem, say if the earth sped up due to a gravitational force, does that mean our individual temperature increases, after all our kinetic energy has increased.

[@kurage_medusa]

Kinetic energy is based on velocity and velocity is relative, so temperature is too. If you accelerate an object in space relative to something else, I believe that it would count as increasing the average temperature of the system, as there would be more kinetic energy available. It would not increase the temperature of the object itself however, since relative to itself the average kinetic energy of its particles is the same.

[@wako1285]

Who else had a teacher who made you type the URL

[@user-eh6eh1od2i]

thought i was the only one

[@korbixszn1191]

yup

[@bellaferreir6732]

UR THE BEST!

[@ProfessorDaveExplains]

you are!

[@narender6464]

Thank you so much 🥰

[@incrediblestudios5609]

I love you Professor Dave

[@raizenvillagracia7644]

Thankyou professor

[@jilliandavenport9404]

Taking my last CSET and need to know this info. Clear ,concise and very helpful! Thank you!

[@asifmandal9758]

Thanks :) Professor Dave

[@eyobwendmagen849]

I rely understand Difference of Temperature and Heat. I like your explanation system. It is easy and nice.

[@abrarmohammed6735]

Thanks 😊

[@waffles_1823]

This is damn useful I even subscribed

[@littletin8453]

the intro is the best i have seen

[@ohmy9261]

You're the man dave

[@rajpanigrahi7008]

Hello Dr Dave... you explain everything in very easy way, so anyone can understand it easily...I am the first to watch and comment on this video.

[@shirohanna]

Great video and visuals. Thank you! Follow up question: The high specific heat capacity of water is due to strong covalent bonds of Hydrogen and Oxygen molecules INSIDE each water atom? Or, strong bonds between water molecules? Thank you, again!

[@abdullahalhabsi9302]

I have an assignment due next week hope similarity doesn’t go high 😅 thank you professor

[@alriktimo644]

Can I say that any system has no need to transfer its energy to the other one in contact but as a natural consequence of action and reaction the energy gets distributed, eventually making the whole system reach equilibrium. Doesn't necessarily imply that energy is transferred from hot to cold and not from cold to hot it is just that the former does the transfer with a faster rate than the latter. Correct my intuition if I am wrong.

[@ghazalabibi9570]

@Professor Dave Explains I love all your highly educational videos that you do here on KZbin. I have a question! How come cold temperatures have a limit of around -273 C and warm temperatures can go well over 10,000 C or even can be over 1 million degrees? Please explain - THANKS.

[@ProfessorDaveExplains]

that's absolute zero! a total absence of kinetic energy

[@kotishjaiman8231]

Just like you can take away only 1 liter of water from a 1 litre beaker but you can keep adding water to it eventually leading it to overflow and you can still just add more. Atoms have a definite amount of energy so you can take away only that small amount, whereas you can give it a lot of heat but after a point its structure will be affected maybe bonds will break (in case of molecules) and after a point you will get plasma.

[@DoubleMrE]

Yay Dave!

[@mamathashaik2452]

Sir ur just awesome sir ur the best sir

[@Meringue_Pie]

saved my life and my science test, thank you

[@sdvsdv4833]

Best lecture

[@jxkeriley.4166]

who here cause of a school lesson

[@amishakahar1282]

your video helps

[@kioo6980]

3:30

[@princerao6525]

can u made a video on optics complete theory...plzz

[@maxamuudsagaar5405]

Good idea

[@nugget...]

You are just great❤

[@IEleMenTIx]

1:20 faster moving particles with higher temperaure ... is correct for gasses and liquids, but not a sufficient expression and explanation for temperature changes in solids. One could misinterprete the statement and think that the atoms will vibrate more often, which is one of the most frequent misconseptions I have read about on scientific websites and forums about atomic motion. Every molecule, molecular solid or atomic solid has characteristic vibration frequencies in the range of 10^13 Hz due to their mass and force interactions. For example: If the frequency of a radiation source matches a molecules or atoms natural resonant frequency it begins to vibrate stronger, not more frequently! Now the energy of those vibrations can be transferred in solids due to whole lattice vibrations called phonons. I'm not trying to give a lecture here. But its such a common misconception that people say if you heat stuff, the frequency of the atomic vibrations increase, which is absolutely NOT true. It's the amplitude of the vibrations that gets larger. Of course this explanation was viewed at with classical mechanics, quantummechanically everything has to do with probability waves and distributions... but the probability of finding a particle will shift towards a higher distance if we give the system more energy. If you look at the asymmetric potential curve you get the idea... The frequency of atomic oscillations simply do not change, otherwise IR-Spectroscopy would not work, as peaks would shift around all the time being a strongly temperature dependant measurement method, which it is not! One thing you can get is overtones of vibrations at higher temperatures... The frequencies which change will eventually be those of the whole macroscopic lattice due to thermal expansion and changes in the elastic modulus of the solid. I think why most people think that atoms change their vibration frequencies is due to incandescence... simply speaking if the amplitude of a vibrating system increases but the vibration frequency stays the same, the particles have to travel a longer distance in the same amount of oscillations. Thus ultimately your statement is correct that the particles have to move faster. Faster moving particles means that more energy is involved... Electromagnetic radiation is generated by the movement of charged particles in space, so at temperatures of around 800 Kelvin our eyes begin to see dim red light emitted from that object depending on its emissivity. At these temperatures the atomic vibrations are so intense that the strong acceleration and deceleration leads to the incandescent effect emitting red light. Plancks law, Wien's displacement law and the stefan boltzmann law are responsible for the shape of the function, the maximal emitted wavelength at a certain temperature and the intensity of the radiation... OK sorry this has escalated to become a lecture ;)

[@ProfessorDaveExplains]

interesting! i see your point with IR, that makes sense. at any rate, this was a little more in the context of gases, but this is excellent supplemental information.

[@IEleMenTIx]

thanks :)

[@sandk7969]

Sound energy make air particles to vibrate and so does solid object.. do sound have some kind of temperature? I mean will sound energy transfer faster in high temperature condition and do otherwise in lower temperature.

[@pram5532]

That has to be the longest KZbin comment I've seen - and not read.

[@xOxAdnanxOx]

Praveen M the longest “ useful “ youtube comment I have ever seen.. u should read it

[@angeliemaebonaobra4448]

Professor Dave! Thank you!

[@rajthegamerz7118]

so long suker

[@rajthegamerz7118]

hey

[@turnitinplagiarismreportch1973]

i have a question what is relationship between heat and flame if you get my point please clarify me!

[@markbendig555]

RAISES the question, not "begs". Please. Love the videos!

[@kabouch]

The covalent bond stretching and bending is an example of potential but not kinetic energy, am I right?

[@sowmyatirunagari1434]

Very helpful..

[@christinetorres8075]

Yea it is

[@aksharasbhat6480]

hi professor dave ,i have one question,if temperature is nothing but kinetic energy why is it considered a base quantity

[@gamingammar3838]

Thanks

[@christianmgbike6188]

When two objects or things are in thermal equilibrium, are their molecules vibrating or moving at the same speeds due to same temp?

[@guidomista3570]

Professor Dave is the Oversimplified of science, change my mind

[@furqankhalid1583]

He is the only reason I stopped hating Physics

[@TheLivirus]

Explain to me the process by which temperature (the average kinetic energy of molecules/atoms) converts into thermal radiation over time.

[@playingsometimes7290]

Nice i can understand it Wow

[@EricPham-gr8pg]

Is pressure and intensity or decibel and compression of space elasticity

[@tsehayenegash8394]

what is the differnce between work done on the system and work done by the system

[@iqrayousaf6898]

My question is if any object having 37 celsius temp and our body has also d same then we will feel any cold or hot sensation or not

[@ProfessorDaveExplains]

if they are at the same temperature there should be no heat transfer.

[@hiroshipascual1691]

amen

[@nirmalmishra6404]

If heat inherently has physical meaning when in transit, constituting its existential definition as a form of energy in motion, what does it truly mean to say that heat 'flows'? When we assert that heat is a form of energy in transit, it implies movement; however, using the term 'flow' seems to redundantly invoke the concept of movement. How can the movement of energy itself be described as 'flow' without introducing redundancy?" I created this analogy to understand what the definition is trying to say:"When we say 'heat always flows from higher to lower temperature until thermal equilibrium is reached,' it conjures an image in my mind of an invisible 'glitter glow' dispersed in the atmosphere(massless being in motion). This 'glitter glow' represents the thermal energy, and with a temperature change, it becomes unevenly distributed. In this mental model, a chunk of the glitter glow with a relatively higher distribution moves towards a lower distribution in a flow, seeking to maintain symmetry as per the Thumb Rule of the universe.The glitter glow is thermal energy and when it flows we say that it's heat

[@sughraagha5551]

Man he don't even blink

[@hammadurrehman9371]

I can't unsee that now...😂

[@johnfeyissa4059]

professor Dave is not a professor his genius in explaining

[@you2tooyou2too]

re 2:30 Not "all" but "generally"; but I'm sure he knows that there are exceptions for some crystalline solids.

[@akrm2944]

Is it better to use High/Low than More/Less kinetic energy in 4:00?

[@ProfessorDaveExplains]

eh, either way!