Salaam..
Today, I would like to share about new knowledge that I have found very interesting in my lecture yesterday. The lecture of Heat Transfer which captured most of my attention as in our group only 13 students in that particular session. The rest of 128 students are in the other session. Great huh? Noise is reduced, hence, focus is increased! =)
Okay, it all started when we all discussed how the heat is transferred from one medium to the other. Well, it's simple for those who is SPM or have learnt Heat Transfer or maybe to those who have just read about it. The heat is transferred through three (3) ways; conduction, convection and radiation. How does it differentiate the three? Conduction happened when the heat entered a static and solid medium, like a wall. So, the method is the molecules in the solid pass the heat to one and another until the heat reaches to the end of the static medium. Lagi senang, fikir main football, passing passing tu kira conduction heat transfer method laa.. Convection on the other hand happens most in flowing fluid. It's like in football, Beckham strike the ball to the goal from the mid field. The heat dissipates in the process. Radiation happens to matter in non zero temperature. Everything in this world radiates even our body! The best radiation absorber will be the PERFECT black body (which doesn't exist!) and the best radiation reflector is the PERFECT white body (which also doesn't exist!). The fact that it is so perfect made them is the reason of their non-existence.
So, somehow, in the middle of the class, someone asked,"Sir, doesn't it the fluid expands when in low temperature?" My lecturer was like having the most unbelievable face that he ever had made in the class. "No, the volume will reduce in low temperature. How can you not know this??"
We also were having the same thought as our lecturer until he added,"Oh..yes..! You are talking about the water volume. Water has different story. What I said just now is for other fluid like gas or other liquid. Well, there's a term called anomalous expansion and that's happened only in water. Imagine you pour water into a bottle and pour until half of the bottle. Close the cap really tight and I mean really really tight. And when you put in the freezer, the bottle will burst out as it cools down. This anomalous expansion only happen at the temperature between 4°C and 0°C."
"Now, I want you guys to go back and finds out what happen to the earth if this special characteristic doesn't exist at all. Give me the answer in the next class," said my Prof.
He also mentioned that once in his numerous lecture's session, he once has had asked this question randomly and one guy answered that,"If the anomalous expansion doesn't exist, we cannot drink lemonade."
Now you wondering why, huh? My Prof said that, it was very brilliant answer from a student. We asked him, why? He said, most fluid contracts as they are cold but water on the other hand, expands as it cools down to 0°C. That's the reason why we can drinks our cool drinks with ice in the drinks.
Back to my Prof question, I am very interested in one answer by a person in the web I browse yesterday. He said,"Ice floats on water, and the water at the bottom of a pool in winter is warmer than at the surface. As a result lakes and ponds freeze slowly from the surface downwards, usually remaining liquid near the bottom, where aquatic life is more likely to survive."
From his explanation, it explains the reason behind of why ice floats on water although we know it is in a solid state already. See, how interesting this small topic can be.
I call this anomalous expansion is the 8th Wonders of the World because without it, world would have no aquatic life for a place so cold like in North Poles. We also cannot drink cold water as it always contracts.
For sekian kalinya, I made myself think of the Greatness of Allah and how Allah so Brilliant in making our earth a place that so perfect for us and other Allah's creations. Subhanallah.. :)
A little sharing of the Quran verses :
p/s : Tak sabar nak masuk class this Friday! :)
Till then..
Wassalaam...
Today, I would like to share about new knowledge that I have found very interesting in my lecture yesterday. The lecture of Heat Transfer which captured most of my attention as in our group only 13 students in that particular session. The rest of 128 students are in the other session. Great huh? Noise is reduced, hence, focus is increased! =)
Okay, it all started when we all discussed how the heat is transferred from one medium to the other. Well, it's simple for those who is SPM or have learnt Heat Transfer or maybe to those who have just read about it. The heat is transferred through three (3) ways; conduction, convection and radiation. How does it differentiate the three? Conduction happened when the heat entered a static and solid medium, like a wall. So, the method is the molecules in the solid pass the heat to one and another until the heat reaches to the end of the static medium. Lagi senang, fikir main football, passing passing tu kira conduction heat transfer method laa.. Convection on the other hand happens most in flowing fluid. It's like in football, Beckham strike the ball to the goal from the mid field. The heat dissipates in the process. Radiation happens to matter in non zero temperature. Everything in this world radiates even our body! The best radiation absorber will be the PERFECT black body (which doesn't exist!) and the best radiation reflector is the PERFECT white body (which also doesn't exist!). The fact that it is so perfect made them is the reason of their non-existence.
So, somehow, in the middle of the class, someone asked,"Sir, doesn't it the fluid expands when in low temperature?" My lecturer was like having the most unbelievable face that he ever had made in the class. "No, the volume will reduce in low temperature. How can you not know this??"
We also were having the same thought as our lecturer until he added,"Oh..yes..! You are talking about the water volume. Water has different story. What I said just now is for other fluid like gas or other liquid. Well, there's a term called anomalous expansion and that's happened only in water. Imagine you pour water into a bottle and pour until half of the bottle. Close the cap really tight and I mean really really tight. And when you put in the freezer, the bottle will burst out as it cools down. This anomalous expansion only happen at the temperature between 4°C and 0°C."
"Now, I want you guys to go back and finds out what happen to the earth if this special characteristic doesn't exist at all. Give me the answer in the next class," said my Prof.
He also mentioned that once in his numerous lecture's session, he once has had asked this question randomly and one guy answered that,"If the anomalous expansion doesn't exist, we cannot drink lemonade."
Now you wondering why, huh? My Prof said that, it was very brilliant answer from a student. We asked him, why? He said, most fluid contracts as they are cold but water on the other hand, expands as it cools down to 0°C. That's the reason why we can drinks our cool drinks with ice in the drinks.
Back to my Prof question, I am very interested in one answer by a person in the web I browse yesterday. He said,"Ice floats on water, and the water at the bottom of a pool in winter is warmer than at the surface. As a result lakes and ponds freeze slowly from the surface downwards, usually remaining liquid near the bottom, where aquatic life is more likely to survive."
From his explanation, it explains the reason behind of why ice floats on water although we know it is in a solid state already. See, how interesting this small topic can be.
I call this anomalous expansion is the 8th Wonders of the World because without it, world would have no aquatic life for a place so cold like in North Poles. We also cannot drink cold water as it always contracts.
For sekian kalinya, I made myself think of the Greatness of Allah and how Allah so Brilliant in making our earth a place that so perfect for us and other Allah's creations. Subhanallah.. :)
Belajar untuk meningkatkan keimanan bukan kesombongan..
kita tetap hamba yang lemah..
Alhamdulillah, Allah has given us new knowledge
which my Prof as the medium to let us know.
A little sharing of the Quran verses :
The Beneficent Allah, Taught the Quran. He created man, Taught him the mode of expression. The sun and the moon follow a reckoning. And the herbs and the trees do prostrate (to Him). And the heaven, He raised it high, and He made the balance, That you may not be inordinate in respect of the measure. And keep up the balance with equity and do not make the measure deficient. And the earth, He has set it for living creatures; Therein is fruit and palms having sheathed clusters, And the grain with (its) husk and fragrance. Which then of the bounties of your Lord will you deny?
(Ar-Rahmaan : 1 - 12)
p/s : Tak sabar nak masuk class this Friday! :)
Till then..
Wassalaam...
2 comments:
salam, kupasan yang sangat menarik.betul ke air boleh ada personaliti bila didedahkan pada persekitaran yg berbeza2?
Salaam.. terima kasih, cuba berkongsi je.. :)
anomalous expansion terbukti dengan mudah bila kita minum minuman berais, bahagian atas permukaan air menyejuk, mnyebabkan molekul yang sejuk turun ke bawah dan molekul yang kurang sejuk naik ke atas. Perasan atau tidak, bila minum teh ais atau apa2 minuman berais, hanye bahgian atas yang sejuk, kita kena kacau supaya dia equilibrium, almost sama2 sejuk, atas dan bawah. Kalau nak lebih lanjut, maybe boleh buat experiment untuk tengok density & volume air bila kita introduce heat dari 0-4 degree C. :D
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