Author Topic: Questions & Facts about Energy  (Read 11311 times)

Srusti.M

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Re: Questions & Facts about Energy
« Reply #15 on: June 11, 2009, 10:28:39 AM »
Swarup Uncle,

These are a lot questions!!

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Now, of course, I am not going to give you the answers, But rather I will ask you to do some homework for me.Follow these three sentences:

Green apples and red apples are ?similar?,
Apples and oranges are different,
Apple and apple pie, latter is ?dependent? on former
Do you agree with these three sentences?..

 
Yes Uncle I agree with these 3 statements. Among Oranges,Green Apples, Red apples, and Apple Pie. 1)Oranges and apples are Different.2) Green apples and Red apples are similar 3) Apple pie is dependent on Apples.

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Now homework is:
Take three words: force, energy, heat? learn their definitions?. Try checking up the units of each?.
You will soon learn three words: joules, calories and newtons?. Match up which word is the units for each term.
Which of these terms and units are like green apples and red apples (that is are ?similar?)?Which of these terms : apple and apple pie?

Energy and Heat are like green apples and red apples. energy and force are like apple and apple pie.

I came to know that Heat & Energy are similar by searching about them and their units. I said that Energy and Force are like apple and apple pie because if there is Energy, there is always Force. So Force is dependent on Energy.
 
Units of Energy,  Calories and Joules  (They used Calories as unit of measurement for Energy & Heat but replaced Calories with Joules)
Force, Newtons
Heat, Calories and Joules (They used Calories as unit of measurement for Energy & Heat but replaced Calories with Joules)

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One more home work, and hope you will like it,  I want you to learn the units for volume? I am sure you know the units of volume of milk you buy, say in gallons or liters?

But what is liter?? Say if you have to build an instrument to measure 1 liter how would you do it? Thinks its your science project?. two clue I will give you is 1) think what is the formula to calculate the volume of cube, and 2) if  liter is ?dependent? on length or ?similar? to length?..

Once you do these two homeworks you will see the broader picture of how to think about these?

The units for volume are Gallons and Liters. 1Gallon = 3.78 Liters.
A Liter is a measuring unit for liquids. If I had to build an instrument to measure 1 liter I would do, I'll use your first clue, Volume Of Cube.
What is Cube?? A Cube is a 3-D object of a square(2-D).
A square has 4, equal, sides. It's flat and only has 1 face. E.X. 12/12 square tile.
A cube has 6 faces. It also has equal sides so it's length, width, and height are equal. But it doesn't have 4 sides. It has 12 sides.  Volume means how much space an object occupies. The formula for Volume of a Cube is L*W*H (Length*Width*Height).
I finally got the equation to how to build an instrument that measures 1 liter!! Here it is:

1 liter = 1,000 ml
Formula for Volume of a cube is L*W*H
Cube has equal sides, so L = W = H.
V = L*L*L
V = L To the power of Cube
1,000 Cubic ml  = L To the power of Cube
 Factor of 1,000
10*100

Factor of 100
10*10

10*10*10 Cubic ml = L To the power of Cube
10 ml = L
L = 10 ml
W = 10 ml
H = 10 ml

Uncle, Liter is dependent on Length of a Cube, because if the lenght grows the Volume grows with it. Suppose we increase the lenght of the Cube by 1, that means it becomes 11ml,  the volume increases to 1,331 Cubic ml. So if we were to build an intrument that measures 1 liter, the length would be 10.
   



Vasu Uncle,

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Dear Srushti.
Why are rocks not hot?: Because there is no *flow* of energy from the rock to you. You feel an object hot when there is a flow of energy from that object into you. Now why would any object transfer energy to me? If the object is agitated. Agitated means the electrons (the negatively charged particles in every atom of the universe) are in a higher state than usual that is they are little farther away from the nucleus containing the protons (positively charged).
Now you see the object doesn't like it So it wants the electrons come back to it's original state. So it will send some of it's energy out so the electrons can come back. So if you touch the object in that state you will be the recipient of that heat.
So this is also the reason any heated object will eventually become cool because it doesn't like to be hot. It wants to be in its natural state: Cool.

If the object isn't alive, how can it have likes and dislikes??



Asterias Annaya,

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As matter is not different from energy. Anything that has matter does have energy. Hence there is energy in anything! Now is there energy even in the "empty" spaces. Think about it !!

Yes, there is Energy even in the "empty" spaces. There is gravity in space right?? And Gravity is a force right?? Where there is Energy there is always Force. So since there is Force in Space there must be Energy.

P.S. Can one of you please explain to me how Einstein's theory is an advantage to us??

"We should not bother about a wish that Baba did not fulfill because we should believe that he did it for our own good. We need strong faith in Baba to believe that he does things for our own good."

Asterias

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Re: Questions & Facts about Energy
« Reply #16 on: June 12, 2009, 08:18:19 AM »
Jai Sai Master !

I am a bit confused Srusti

1. Energy and Heat are not similar! Heat is a form of energy .. a type of energy. I would equate Energy to apples and Heat to green apples. Please correct me if i am wrong

2. You say that when there is energy there is force and hence if there is force there must be energy!! Thats a logical jump.

Do you mean Srusti is little girl means all little girls are Srusti!! :) I am not saying that the conclusion you have come to is wrong, I am just saying that just because A implies B (i.e. A suggests B) need not necessarily mean that B suggests A. Another example - If its raining, we can safely conclude that there were black clouds before the rain started, but each time black clouds come, it need not rain !

--x--

Dear Sai bandhus

I am not a scientist. I have done BE in Electronics and Communication. And thats about as far as my brush with science and technology goes. However, as a layman .. I find it extremely hard to understand when someone says ..

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One good way to think/understand any physics term would be think of four things:
What are the units of that term,
From units how does the definition fit in,
Is the quantity scalar or vector,
What are the limits of the term.. (for eg, you will read in a definition, something like.... for a given system... in ideal conditions...etc, so what is given, what is ideal for that definition)

Along with this try to read up on definitions of : matter and space

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In those cases of bias between any two terms, and that?s when, what sai_prince told, holds good. And that is, look at the units of each. (not just simple definitions, of course critical analysis of the definition also leads you there) But looking at units is more easier and atleast I follow this way in my regular practice.

And a golden rule is anything when the basic units are same are interchangeable or ?similar?. When one unit is derived from other it is ?dependent?.

This is precisely the way, IMHO, science should NOT be taught.

1. Teaching dimensional analysis, units and what not for explaining some of the elementary concepts in physics!! Wow I thought this was one of the cheap tricks used to get answers for EAMCET exams.

2. I have tried to go through a lot of articles (on wikipedia - may be not the best resource), still I could not come up with a definition for mass and weight. If some one can .. please define TIME and SPACE.

There is science and there is maths. To think of science in terms of maths is almost killjoy. To make something so natural into something totally abstract, does no good. And this a tendency I have seen with many mathematicians and physicists on other forums. They give formula instead of words, they give derivations instead of explanations.

Atleast from a layman perspective, it makes NO sense at all.

These are the humble opinions of a scientific lay man. Please pardon me.

Jai Sai Master !




Ananth

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Re: Questions & Facts about Energy
« Reply #17 on: June 12, 2009, 12:11:41 PM »
Jai Sai Master, Babu garu..
Jai Sai Master, Sai Bandhus..

Jai Sai Master, Asterias garu..

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There is science and there is maths. To think of science in terms of maths is almost killjoy. To make something so natural into something totally abstract, does no good. And this a tendency I have seen with many mathematicians and physicists on other forums. They give formula instead of words, they give derivations instead of explanations.

Atleast from a layman perspective, it makes NO sense at all.

Being a non-scientific person, I agree. I am also curious as to how Scientists would think of this view. The non-mathematical view of science.

Regards,
Jai Sai Master!
Jai Sai Master!
Jai Swamy Sai!

sai_prince

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Re: Questions & Facts about Energy
« Reply #18 on: June 13, 2009, 12:18:43 AM »
I am not a scientist too.  I have Masters in Biochemistry; and for masters thesis I have approximately 2 yrs of research lab experience. My knowledge ends there. I always wanted to do PhD. But given my financial situation and family obligations I started a job hunt. I still think some day i want to go back and do PhD. It is nice to know there are several PhDs on this forum.

As far as the questions on this thread are concerned, and based on my limited knowledge, I am reasonably sure/ or rather think what I wrote is correct... or atleast this is the way I was taught. Although I have some explanations/reasons told to me, I would rather not discuss and wait for some real scientist to discuss it.

Jai sai master
 

Srusti.M

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Re: Swarup Uncle's opinions
« Reply #19 on: June 13, 2009, 09:53:36 PM »
Swarup Uncle wrote:

Dear all,

Please note that the following is not intended to argue against anyone, but just to improve our basic understanding. Also, dear Srusti please follow along and I will come with specifics to you latter:


MAN ?OOOhhh? MAN???.
 

?KILLJOY?????.  ?CHEAP TRICKS in eamcet?? ?. ?Mathematics is abstract?
 

Gosh of Gosh?. May be its not the kids who need the orientation, may be it?s the ?elders? who need it. I am not sure on the tricks I used in my eamcet, as its been ~14 years, but I was able to get through eamcet in first attempt in and secured a seat in osmania medical college in the so-called open category.
 

The first chapter in Resnick and Halliday textbook is units and dimensions and also the first thing we learn in inter first year physics is units and dimensions?..  Its my understanding that Resnick and Halliday were too respectable to teach to be cheap.
 

One simple example, how many of us saw what our 11 yr old wrote above ?.. We were picky enough to point out the difference between heat and energy etc?  But why did the units of  length written wrong seven times skipped our notice?? Its ok if a 10 yr old does that mistake, but if we ?elders? do it than no excuse????
 

Why was it difficult for us to pick up its not 10 ml*10 ml* 10 ml which makes 1 liter, but, its rather, 10 cm* 10 cm* 10 cm which makes one liter?.. Why did we fail to see its not 1000 cubic ml which makes 1 liter but rather 1000 cubic cm which makes one liter?.. Immediately after seeing cubic ml the thought should be: Can cubic ml, or in other words cube of volume, be unit for any direct parameter??
 

This should by in itself question our understanding?.. Now if we are answering ourselves: ooo? that was too minor of a detail, we saw ml but we thought it was cm, than more than likely we are cheating ourselves. The fact is we paid attention to number 1000 which makes sense and units which is equally important is neglected?? More than neglected, this happened because we don?t realize the importance?
 

Also, I completely fail to agree it was a typo, I think simply it was not taught to our kids?.. and elders and teachers should take direct blame? no excuses? period
 

Dimensional analysis is like grammar to science jargon (not just physics). We learn basic words first and are immediately introduced to grammar. Similarly, after basic knowledge in science, we immediately get the first lesson in 11 th grade and that is dimensional analysis?.
 

If not much, atleast we elders have to learn it to teach our kids J
 

But I strongly think its too late than and has to be introduced in a basic way from middle school itself (of course this sentence is my opinion)
 

If someone analyzes a quantity with respect to units, I think its an intelligent way (or rather basic level) and definitely not cheap trick?..
 

Now coming to weight, why is it hard to analyze?? Just because we did not even do the basic reasoning?. What is weight? Mass pulled in the direction of gravity; What are its units ..Kg.weight?. true more specific?. Mass times g (where g is acceleration due to gravity). We know from newtons second law mass times acceleration is force. So what is weight? A kind of force. Going back again weight is mass pulled in the direction of gravity, we also know PULL or PUSH is force. And weight is ?dependent? on two parameters. Even if we know nothing just units will tell it all.
 

Now, if we take energy and states of energy, we describe entropy, enthalpy etc, what are those?? If we question that go back to units, units of entropy, enthalpy are energy, so essentially those terms describe the various energy states of matter. Because the units are same they could be added or subtracted; this rule we learn it in third grade we add apples to apples. All this understanding comes of quickly only if basic dimensional analysis flows fluently.
 

This understanding is the basic step required which will enable us to equate to things. Because equating is between two equals and we need to know what is equal between two. That too especially to learn details of electromagnetic photonic energy i.e., energy in a perpendicularly oriented electric and magnetic field  this basic understanding is taken as common sense.
 

Also, I don?t think Maths and science are two different things, Maths is a kind of science and very much an integral part of science?.
 

Finally, to my understanding and based on my 4-5 yrs of teaching experience I am pretty sure teaching dimensional analyse is the correct basic step to higher understanding...  and Definitely I would not recommend going forward into the fancy space-time continuum jargon without a clear understanding on the dimensional analysis.
 

To Dear Srusti,

I am sure what you wrote could be a slip, and you can easily correct it.

Btw, the way you wrote it sounded correct to me. But I want you to learn it that is correct and not a slip J Let me suggest you some more things so that the concept is clear.

You said joules and calories are inter-convertible. Check what is the conversion.
 

Now try to determine what is the connection between the three that is:

1)      What is the relation between Newton and Joule

2)      What is the conversion between Joule and calorie

 

Again these could be a bit too high for a 10-11 yr old. Don?t bother about the details. Just analyze the units and try to see if there is a connection based on units between force and energy. If you do this you will see a broader picture how mass, time and length interrelate to act to get force, and energy, and also helps you to get a grasp when we talk about any concept on energy Einsteins concept being one of them.
 

To tell you the advantage of Einstein?s theory; scientists until 1900 were perplexed with how to describe light. Like, its common knowledge that plants take up light (as energy) for photosynthesis. So the question was how to define energy in light?? Einstein with several other contemporary scientists tried to define this light and energy with it and interconvertable nature of energy. Previously light was considered to be moving in a form of wave like sound wave, for example. But the velocity of light is several millions of times higher than sound.
 

Einstein solved this mystery on the source of energy in light wave, by giving the particle nature to light. That is to say, light is particles or packets of energy.

Now follow the logic carefully:

once we say packet it becomes an object, right?

Object is considered matter

Any Mater should be defined with two terms, mass, and volume

Volume as you have said earlier is dependent on length

So light is energy defined with mass and movement in length

Movement or velocity (or as a rough word-speed)  has length and time in it

So again energy is dependent on mass and velocity

Other words energy has mass, length and time in it

 

Now one more time  lets do it backwards again:

Energy has Mass. Length and Time (last senetence)

Volume has Length in it.

Anything with volume occupies some space

So energy has mass volume and time

Volume is space---So, Energy has space in it

Mass and volume are objects or matter---- so matter has energy

 

This is famously called Particle theory or Quantum theory

 

Now you see how much it has got to do with dimensional analysis?.

 

May be all the senetence I wrote may not mean much to you now, but atleast the take home message for any kid including myself (as I do these mistakes several times myself) Whenever you see something critically analyse the dimensions; and for known terms if we are not clear on units, we know nothing? period.

 

Now I think my maths teachers in school were very nice when I forgot to write the units; as they took out just half a point for not writing units. If I grade someone and they don?t write units I feel like giving them a Zero   (ofcourse I don?t do it)

 

Now after all this jargon Srusti, you are wondering what good is it to now if energy is matter or converts to one form to other. Lets think about it:

 

You said energy can be interconvertable (say heat vs energy).

Now if that is true any energy is like say, electric energy, magnetic energy, heat energy  all are interconvertable. And that is precisely true. Take any sound instrument, ipod, or olden days radio, all work on this principle, conversion of electromagnetic energy to sound energy.

If light is particle as we discussed we should be able to obstruct(or come in between) it just like any object right, that is the principle used in X-ray picture taken to test for fractures.

Light is energy and heat is energy there should be a conversion , and that is seen in microwave ovens. Electric energy converted to electromagnetic converted to heat.

 

The flip side and the evil side of discovery:

Now we said matter is energy, I think you know the fundamental particles are atoms? so atoms are energy?. That?s were comes the deadly atom bombs? Conversion of matter to energy - atomic energy can cause high impact destruction. That is the principle of angels and demons movie.

 

May be I wrote a lot today, and may be you will not understand all, but the least I want you to learn is next time you learn new things analyze the details and should be crystal clear in the concept.  Next time you see any object and instrument be it piano, guitar, videogame, fridge etc.. try to learn why and how it is doing that, rather than a given assumption, it just does that?.

 
Finally as always, thanks to our dearest srusti for agreeing to post this message.
 
Om sai ram

Swarup
"We should not bother about a wish that Baba did not fulfill because we should believe that he did it for our own good. We need strong faith in Baba to believe that he does things for our own good."

Asterias

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Re: Questions & Facts about Energy
« Reply #20 on: June 13, 2009, 10:17:33 PM »
Jai Sai Master !

Dear Swarup garu,

Please define for me what is

1. Mass
2. Weight

I am equally unclear on what Energy, force etc are, however since you are going about them in a structured way, I intend to follow along.

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The first chapter in Resnick and Halliday textbook is units and dimensions and also the first thing we learn in inter first year physics is units and dimensions?..

Oh so now, our education system is perfect!

And btw, Richard Feynman's Lectures on physics dont seem to start with dimension analysis - Was it a mistake ??

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Dimensional analysis is like grammar to science jargon (not just physics). We learn basic words first and are immediately introduced to grammar. Similarly, after basic knowledge in science, we immediately get the first lesson in 11 th grade and that is dimensional analysis?.

Oh! I am not a scientist, but I do teach English and have never had to teach anyone grammar to understand English. One should understand that grammar in itself tends to be so confusing, with each rule going against another rule and hence another rule, that its highly advisable NOT to teach anyone based on grammar.

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One simple example, how many of us saw what our 11 yr old wrote above ?.. We were picky enough to point out the difference between heat and energy etc?  But why did the units of  length written wrong seven times skipped our notice?? Its ok if a 10 yr old does that mistake, but if we ?elders? do it than no excuse????
 

Why was it difficult for us to pick up its not 10 ml*10 ml* 10 ml which makes 1 liter, but, its rather, 10 cm* 10 cm* 10 cm which makes one liter?.. Why did we fail to see its not 1000 cubic ml which makes 1 liter but rather 1000 cubic cm which makes one liter?.. Immediately after seeing cubic ml the thought should be: Can cubic ml, or in other words cube of volume, be unit for any direct parameter??
 

This should by in itself question our understanding?.. Now if we are answering ourselves: ooo? that was too minor of a detail, we saw ml but we thought it was cm, than more than likely we are cheating ourselves. The fact is we paid attention to number 1000 which makes sense and units which is equally important is neglected?? More than neglected, this happened because we don?t realize the importance?
 

Also, I completely fail to agree it was a typo, I think simply it was not taught to our kids?.. and elders and teachers should take direct blame? no excuses? period

I, for one, never read the whole post properly. I just read what I found interesting in the post. I am not here to teach anyone. I am here to improve my understanding. I am very happy that Srusti started this thing. It is helping me understand all the things that I thought I knew. However if you want to blame me for overlooking some mistakes she did in units etc, well frankly I wont make such a big issue of it.

Units and dimensions have their place in physics, no questions about that. But I do need some "orientation", if I have to teach somebody physics in that manner.

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Now coming to weight, why is it hard to analyze?? Just because we did not even do the basic reasoning?. What is weight? Mass pulled in the direction of gravity; What are its units ..Kg.weight?. true more specific?. Mass times g (where g is acceleration due to gravity). We know from newtons second law mass times acceleration is force. So what is weight? A kind of force. Going back again weight is mass pulled in the direction of gravity, we also know PULL or PUSH is force. And weight is ?dependent? on two parameters. Even if we know nothing just units will tell it all.

Ah, by your own logic, how come you overlooked my question, I specifically asked for mass and then weight. You seem to talk abt weight, but what is mass! You never answered that.

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Finally, to my understanding and based on my 4-5 yrs of teaching experience I am pretty sure teaching dimensional analyse is the correct basic step to higher understanding...

Depends on what you define "higher" understanding as.

Jai Sai Master !

ps: I think may be this is not the appropriate board to discuss what I feel regarding this, I will stop this discussion here itself. Also I think Swarup garu, you must be pretty tied up with your own research. We can continue this discussion when you are free. No hard feelings!

sai_prince

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Re: Questions & Facts about Energy
« Reply #21 on: June 13, 2009, 10:53:56 PM »
I think the intent was not about blaming, or making an big deal, rather It is an inherent tendency we dont care about the most important things, which I guess is Swarup garu pointing out. Which as he says is pretty common in the initial stages, and we have to be careful, especially when the context is made as such going higher stage in the topic. I didnot notice that but it was clearly because I didnot think it was that important, I agree these culminate to bigger mistakes.

What is Mass?? I am not even sure if its a serious question. Those are the standard units of measurement which were taken and we take that as a starting point. Mass is a term used to describe an object as compared to one standard metal alloy or something like that...

How how correct is that standard unit?? I am totally not sure if its a bashing thing or serious thing.
Now I can ask what is alphabet 'A',  define 'A' for me before we write words and paragraphs....

Now again perfection of education system and correctness in teaching grammar I really dont understand the logic.

I myself I am not smart enough to explain, but this I am not sure if whats going on is bashing or debating or reasoning or arguing

Sorry guys, I am totally confused, and don't know where this is going.

Jai sai master.
« Last Edit: June 13, 2009, 11:05:42 PM by sai_prince »

Asterias

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Re: Questions & Facts about Energy
« Reply #22 on: June 13, 2009, 11:12:53 PM »
Jai Sai Master !

Dear Sai_prince garu,
Quote
I myself I am not smart enough to explain, but this I am not sure if whats going on is bashing or debating or reasoning or arguing

Sorry guys, I am totally confused, and don't know where this is going.

The intention was not that, however it did seem to become that. Anyways, I dont intend to raise any further questions.

Jai Sai Master !

Dwarakanath

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Re: Swarup Uncle's opinions
« Reply #23 on: June 14, 2009, 07:14:06 AM »
Quote
The first chapter in Resnick and Halliday textbook is units and dimensions and also the first thing we learn in inter first year physics is units and dimensions?..  Its my understanding that Resnick and Halliday were too respectable to teach to be cheap.

-------------- Well, the question is not about whether Resnick or Halliday were cheap.. Its just that some tricks used to finish some problems fast - irrespective of understanding the problem - is cheap. Besides, resnick and halliday are not the end all be all of science. There are other ways of learning things, than just physics, maths or chemistry. I dont mind kids being taught 'units' or 'dimensions', etc. But they should be encouraged to 'figure things out' rather than just 'here are the formulae.. do it that way'. I loved it swarupgaru when you started talking about apples. Thats the right way to go about it, IMO. Please go ahead with what you are doing. May be, after you are somewhat done, I will try and talk the intuitive side of things with Srusti. Otherwise, she might get confused.



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?.. and elders and teachers should take direct blame? no excuses? period
 
------------------------ True. Completely agreed. Elders and teachers are the ones to blame. Blame my teachers.. :D ;)


 

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If someone analyzes a quantity with respect to units, I think its an intelligent way (or rather basic level) and definitely not cheap trick?..

--------------------------- Very True. But thinking ONLY in terms of units (quantity) is not the complete story.

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Now coming to weight, why is it hard to analyze?? Just because we did not even do the basic reasoning?. What is weight? Mass pulled in the direction of gravity;
---------------------------- Not just that!!! Weight is NOT just mass pulled in the direction of gravity. Weight is what WE FEEL when we hold an object (Also, it has effects on other objects too.. which we percieve - say, paper weight on papers). THE REASON for what we feel is "MASS BEING PULLED IN THE DIRECTION OF GRAVITY". Weight is just the relationship between several objects. 'Units' are a way to measure its effects, thats all. The reason for weight is - pulling by gravity (or some other force). Weight is what we feel (or what some other 'obstructing' object faces) when we try and oppose that pulling. Units are a way to measure it.
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So what is weight? A kind of force. Going back again weight is mass pulled in the direction of gravity, we also know PULL or PUSH is force. And weight is ?dependent? on two parameters. Even if we know nothing just units will tell it all.
 
Weight cannot be argued to be a 'property' of that object  (in different gravitational pulls, the same objects weighs differently). Nor is it a force in itself (an object doesnt loose energy just because it is exerting weight). Starting with what we know is a better place than ' UNITS ' for kids IMO, rather than starting with units.
 
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Now, if we take energy and states of energy, we describe entropy, enthalpy etc, what are those?? If we question that go back to units, units of entropy, enthalpy are energy, so essentially those terms describe the various energy states of matter. Because the units are same they could be added or subtracted; this rule we learn it in third grade we add apples to apples. All this understanding comes of quickly only if basic dimensional analysis flows fluently.
 
------------ Dimensional analysis, as you explained, helps in 'calculating' or 'understanding' things. No doubt. But what are fundamental dimensions in such an analysis? Why are they fundamental?? Kids need to be told about THAT one!!

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This understanding is the basic step required which will enable us to equate to things. Because equating is between two equals and we need to know what is equal between two.

----------- Equating two equals, we need to know what is equal between two. True. What is equal between analysis (mathematics, units) and understanding?? We have to hit that common ground for 'units' to even make proper sense. Why do we use units, How do we use them, etc.

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Also, I don?t think Maths and science are two different things, Maths is a kind of science and very much an integral part of science?.
----------- Agreed. Math is an integral part of Science (certain parts of science). Its a tool to understand things better. There are other ways to understand things, which when looked at along with the 'maths' way, gives a more complete understanding.

 
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Finally, to my understanding and based on my 4-5 yrs of teaching experience I am pretty sure teaching dimensional analyse is the correct basic step to higher understanding...  and Definitely I would not recommend going forward into the fancy space-time continuum jargon without a clear understanding on the dimensional analysis.
 
---------- True. From a 'student' point of view, I would love it if the teaching is grounded in what I can see, feel, and understand and then build up on those. Also 'Higher Understanding' happens the other way too. The Intuitive way. Using the kids imagination and intuition to understand and then the 'scientific method' to look at things more clearly and understand particulars. Ignoring one and exalting the other is not so smart, IMO. For example, a sound understanding of what multiplication/division means is needed before we jump into algebra, progressions and other things.   


Anyways,
I just wrote it so that srusti can understand that there is another way of understanding the world. Not just the 'physics' or 'chemistry' or 'maths' way. Those are good and necessary, but so too is this other way. Besides, without this 'other way', there cant be any 'physics' or 'chemistry' or 'maths'. They all came from this 'other way', a way of looking at things honestly and earnestly and trying to "COMPREHEND" rather than just mug up formulae or units and reproduce.

Resnick and Halliday is one way. Veda Ganitam is another. Sankhya Yogam is another. Psychology and cognition, yet another. Self analysis is yet another. Logic is yet another. Hope srusti learns ALL of them!!

Jai Sai Master!!

Dwarakanath

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Re: Questions & Facts about Energy
« Reply #24 on: June 14, 2009, 07:22:49 AM »
Jai Sai Master!

Oh.. by the way.. Terrific explanation swarupgaru!! I love what you wrote to srusti!

Jai Sai Master!!

Asterias

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Re: Questions & Facts about Energy
« Reply #25 on: June 14, 2009, 07:49:27 AM »
Jai Sai Master !

Quote
Resnick and Halliday is one way. Veda Ganitam is another. Sankhya Yogam is another. Psychology and cognition, yet another. Self analysis is yet another. Logic is yet another. Hope srusti learns ALL of them!!

My best wishes too.

Jai Sai Master !

vasu

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Re: Questions & Facts about Energy
« Reply #26 on: June 14, 2009, 11:00:20 AM »
Jai Sai Master!
I love Resnick & Holiday book. I think if I remember correctly, the authors also suggest in the introduction that units and dimensions chapter be taught after initial introductory topics like speed and velocity etc (if I remember correctly).

I think EAMCET is good at judging your grip on the subject. Speaking on the grip, all these subjects are to get some grip on how things happen in this world. Now coming to the question why they happen: Only Sai knows (nuvvu choosedanta kalisi nenu perhaps)

Srusti:
That's why even though object is not alive, I chose the word 'like' to describe the behavior of the atom that's fried (heated). When we describe things in terms of atoms, there is no question of life and death right. Even living entities like us are combination of atoms (outwardly).

Jai Sai Master!
« Last Edit: June 14, 2009, 09:09:25 PM by vasu »

Srusti.M

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Re: Questions & Facts about Energy
« Reply #27 on: June 14, 2009, 11:30:05 AM »
I have one small question. Any 3-D object that occupies space has volume. But Uncles don't 2-D objects occupy space too?? Then why don't we say that 2-D objects have volume. Some people say there is that only 3-D objects have volume. Anything that is matter occupies space. For E.X. if we have a rectangular shaped photo frame is a 2-D object but it occupies space. Right??   
"We should not bother about a wish that Baba did not fulfill because we should believe that he did it for our own good. We need strong faith in Baba to believe that he does things for our own good."

svelagal

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Re: Questions & Facts about Energy
« Reply #28 on: June 14, 2009, 12:24:17 PM »
Dear saibhandus

its been long time i had gone through these forums. as i opened the forum and saw the discussion about enrgy i felt bad for not seeing this forum for long time. i wish i should follow these threads to learn many things.

Swarup gari explanation made me to bring my past memories of college days. we used to calculate electricity unit calculations by seeing the watts on bulbs and elecrtic items ( 1 kilo watt hour= 1 unit )

I always had a doubt about the units of energy, as every one says one form of energy will be transfered to another form.   like if i say units of energy is calories, is this mean electric enrgy or light sound or heat or food?
I came recently to US ,and here every person says food in terms of calories. how many calories you ate and how many you have burnt doing gym?

Quote
I have one small question.
Srushti, A question is always a question, there is no small or big. (this is what i was taught when i was at your age >:()
Quote
Any 3-D object that occupies space has volume. But Uncles don't 2-D objects occupy space too?? Then why don't we say that 2-D objects have volume. Some people say there is that only 3-D objects have volume. Anything that is matter occupies space. For E.X. if we have a rectangular shaped photo frame is a 2-D object but it occupies space. Right??
You are right a 2d object also occupies space, but we call it as Area rather than volume, also you can say the volume is ZERO.
simple calculation
let us say
photo frame has length =20 cm ( )
breadth  =10 cm
Hieght = 0 CM

Volume = 20 cm * 10 cm* 0 cm= 0 cubic cm
Sawrup garu,
I hope i used the correct unit of measure  ;)

Please forgive me if i had mentioned any thing wrong.

OM SAI RAM
 
Regards,
Sateesh


!!!Sarve janaa Sukinoo bhavantu!!!!
!!!Samasta sanmagalani bhavantu!!!

Srusti.M

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Re: Questions & Facts about Energy
« Reply #29 on: June 15, 2009, 11:33:52 AM »
Svelagal Uncle,

Quote
Srushti, A question is always a question, there is no small or big. (this is what i was taught when i was at your age Angry)

I agree.

Quote
You are right a 2d object also occupies space, but we call it as Area rather than volume, also you can say the volume is ZERO.
simple calculation
let us say
photo frame has length =20 cm ( )
breadth  =10 cm
Hieght = 0 CM

Volume = 20 cm * 10 cm* 0 cm= 0 cubic cm
Sawrup garu,
I hope i used the correct unit of measure  Wink

Please forgive me if i had mentioned any thing wrong.

Uncle, I know that anything multiplied by zero becomes zero, and 2-D objects don't have any height so the value of length and width is multiplied by zero since the object doesn't have any height and you get zero the object's volume.

Thank you very much for your explanation, but it was not what I was looking for.....

Maybe I didn't frame my question properly, what I mean to say is, the space occupied by a square is Area and the space occupied by a cube is Volume. I don't exactly know the definition of Area, but I know it's the space inside the square. Is it right??

so What is the difference between the area and Volume, because both occupies space??

I know we calculate area for 2-D objects and Volume for 3-D objects, but what are they exactly??

Vasu Uncle,

Maybe you are right, there won't be any likes and dislikes in Atom level.

Asterias Annaya,

I'll answer your questions very soon. May be my logic is not perfetct, i need to think about it.
« Last Edit: June 15, 2009, 11:54:42 AM by Srusti.M »
"We should not bother about a wish that Baba did not fulfill because we should believe that he did it for our own good. We need strong faith in Baba to believe that he does things for our own good."