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Old Nov 5th 2015, 03:29 PM   #11
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Originally Posted by MBW View Post
I thought your initial answer was quite good
You do flatter me, Sir


Originally Posted by MBW View Post

I must however take issue with the "thermal energy just created out of nothing" line.

I said this because i can't understand what heat is. Heat is not a physical thing you can imagine picking up like an electron. So what is heat? What is energy. I can feel heat from a heater but what is it that's hitting my body. Is it infrared radiation?

Last edited by Hero; Nov 5th 2015 at 03:32 PM.
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Old Nov 5th 2015, 03:39 PM   #12
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Heat is the kinetic energy of the individual atoms or molecules.
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Old Nov 5th 2015, 03:45 PM   #13
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Originally Posted by MBW View Post
Heat is the kinetic energy of the individual atoms or molecules.
Fantastic. A simple sentence that tells me so much. I've been searching the internet for the last few days looking for the answer and found just pages of meaningless text.

Thank you. That explains so many things now. The world of physics is making sense.

Friction causes is heat because ...
Originally Posted by MBW View Post
Heat is the kinetic energy of the individual atoms or molecules.
Compression of a gas causes heat because ...
Originally Posted by MBW View Post
Heat is the kinetic energy of the individual atoms or molecules.
Fantastic
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Old Nov 5th 2015, 03:52 PM   #14
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MBW I've made your phrase my signature .... if you don't mind.

Take a look at the downwards.



Now back to my original question .... still confused and looking for a simple answer
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Old Nov 6th 2015, 12:24 AM   #15
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Energy is transferred from KINETIC ENERGY in the shuttle to KINETIC ENERGY in the air molecules when they are pushed by the shuttle to THERMAL ENERGY from friction between the air and shuttle.

Not to The friction would occur in any case.

More KINETIC ENERGY is lost by the resistance to compression of the air.

This is not a different effect.

Some THERMAL ENERGY is lost from the air into the other air all around.

Lost from the air to the air, please rephrase eg is resdistributed within the air mass/body.

THERMAL ENERGY from the air that has just been has just been given energy by the shuttle is transferred the shuttle that gets hot too.

No the shuttle heats up because work is done by the forces of friction.
Have you come across work or momentum?

Energy is transferred from the shuttle to the air body by menas of momentum trnasfer.
The work done by the dissipative forces of friction heats both the air and the shuttle.
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Old Nov 6th 2015, 08:03 AM   #16
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Springfield Rifle Musket

Hell again Hero,

I was thinking about your request for a "... short description of reentry."
A range of ideas were expressed. Nonetheless you've gotta go to class sometime soon. Right?

So I suggest a simpler topic. Did Civil war Minieball bullets melt
when they hit solid as a bone or tree?

This discussion is sound physics.

http://www.thermospokenhere.com/wp/0...et/musket.html

Good Luck to you. TSH
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Old Nov 6th 2015, 02:39 PM   #17
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Originally Posted by THERMO Spoken Here View Post
Hell again Hero,

I was thinking about your request for a "... short description of reentry."
A range of ideas were expressed. Nonetheless you've gotta go to class sometime soon. Right?
Hello Thermo,

I'm going to summarise all that I've concluded in the next few days because I've got to end it. Driving me crazy. I need an answer worthy or a 9/10 score or 8/10 at worst. Just high school physics level stuff with simple thoughts about friction, heat, radiation. I just need an answer

I'd be grateful if someone could give me an answer with BLANK SINGLE WORD SPACES to fill in. Like dot-to - dot
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Old Nov 7th 2015, 04:42 PM   #18
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Space shuttle enters the atmosphere. (i) What happens to the transferred energy?

The shuttle is travelling very fast when it enters the atmosphere so needs to reduce its kinetic energy so that it reach a safe landing velocity.
Some the kinetic energy of the space shuttle will be used to compress the air molecules (I don’t know what the energy causing the compression is called or what energy the kinetic energy has been converted into). This slows the shuttle down.

As the shuttle loses energy, the air molecules will be gaining energy when they are hit by the shuttle … so the shuttle has transferred it kinetic energy into kinetic energy of of the air molecules.
Compressing a gas causes it to heat. So some of the shuttle’s kinetic energy has been converted into thermal energy of the air molecules. The radiant heat from the air that has been heated (by the compression) begins to heat the incoming shuttle itself ….. another transfer of energy.

(ii) how do the high temperatures generated in the shuttle enters the Earth atmosphere relate to the material used for the underside of the shuttle surface? Why is the underside not made from aluminium or iron?

Clack silica (a product of sand) tiles line the under-surface of the shuttle, that are able to protect the craft because they are thermal energy insulators (poor conductors of thermal energy) so will not heat up and have a high melting points.
Metals such as aluminium (melting point 660 C) and iron are not used because they are thermal conductors and would heat up and melt under the immense heat.


Above are my amended answers. I think I'm going around in circles. This answer sounds similar to my original answer despite trying to understand what's being said and despite research on the internet. So perhaps its reasonable to conclude i'm not getting it. I need more help .... or just the answer now. Please
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Old Nov 8th 2015, 03:48 AM   #19
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Yes, Hero, you are going round in circles because you as suffering under some basic misconceptions.

Why did you not respond to my post15?
In particular I asked you if
Have you come across work or momentum?
You have posted this in high school physics.

In high school you should have heard of Boyle's Law?

The upper atmosphere is so thin that it is almost exactly a perfect or ideal gas - This means that it does not heat up under compression.

This is not a criticism if you have not heard of work, Boyle's Law, or momentum.
This is an attempt to find a level of explanation that will fit your knowledge of physics.
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Old Nov 8th 2015, 02:35 PM   #20
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Originally Posted by studiot View Post
Yes, Hero, you are going round in circles because you as suffering under some basic misconceptions.

Why did you not respond to my post15?
In particular I asked you if
My sincere apology for not answering your question. I thought you were going to take me off topic and I was l already quite confused without WORK and MOMENTUM being thrown in the mix .... quite rude of me to make that assumption.

This is just a courtesy post so that you know that I have seen your comment. I will answer in full tomorrow because I really have to go right now.
PS I have heard of Boyles Law

Thanks for your help thus far
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