Struggling with Meaninglessness

searching meaning in meaninglessness

Archive for the ‘Physics’ Category

Law of Thermodynamics

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First Law of Thermodynamics

Putting it simply – Energy cannot be created out of nothing and cannot be destroyed to nothing.

The basic idea here is you can manipulate energy to change from one form to another – for example, using electricity to boil water (heat) or burning petrol to move a car. Or even converting energy to matter and vice versa.

As i have said, energy and matter cannot be totally destroyed. Many times, matter and energy were merely ‘transforming’  from one form to another. Let’s take a scenario for instance – you want to eliminate all evidences on a piece of paper. So you take a lighter, ignite the paper and burn the paper to ashes. From our human perspective, we have practically destroyed the paper. But from physics point of view, the paper has just undergone a transmutation process. The amount of energy and matter mass before and after the paper was burn will always be the same. This is called the equivalent principle.

Basically:

Mass of Paper + Mass of Fire (Lighter) + Mass of Oxygen = Mass of Ashes + Mass of Carbon Dioxide + Mass of other after-burn gases (Smoke) + etc.

Therefore, the amount of energy we have since the first day when the universe was born (presuming from big bang) will always remain the same throughout the life span of the universe (billion of years). Energy will just keep on recycling and transforming to another forms over and over again.

Second Law of Thermodynamics

There are two implications from this law.

1. Centralized energy will always disperse and spread out.

2. The total amount of entropy (disorder) in the universe will always increases. Practically everything and anything.

The second law of thermodynamics deals with everyday human experience. Using back the example of burning paper, notice that whenever you light up a piece of paper, the fire will not just remain on a spot but will always spontaneously spread all over the paper. Likewise, the smoke will disperse to the surrounding instead of just remaining on a spot. 

Hence, this process will lead to entropy. Basically, everything in this universe goes from order to disorder, but not the opposite. You can burn the paper to ashes, but not assembling back the ashes to a paper. Human will age and die. but you can’t revive the dead and vitalize the youth on a person. Everything seems to move in a single direction, dictate by cause and effect. (Unless we could reverse time)

Richard Feynman once questioned – Why do we remember the past but can’t remember the future? This is not a stupid question. I can tell you the implication is much deeper than we think it is.

An example of Entropy: The Sun produces energy from nuclear fusion activities and shine light and heat across the galaxy because according to the Second Law of Thermodynamics, the heat, light and other form of energy must disperse. Therefore, the Sun will have to constantly produce energy to sustain the energy output in every moment. That means, someday one day, the resources on the sun will eventually deplete and run down.

Theoretically, if the Sun do not disperse energy, the Sun could live forever and will not die. (Though it is impossible not to disperse energy as everything has to obey the Second Law of Thermodynamics)

Third Law of Thermodynamics

Nothing can reach absolute zero temperature. That’s all i know about it =P.

Why is Thermodynamics important to our everyday life?

1. Understanding how matter and energy works.

2. I always believe that any philosophy which can be derived by observing how the nature work will be a good philosophy.

Written by elan85

March 4, 2008 at 3:38 pm

Posted in Physics

Motion @ space

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(This is a continuation from my previous post …)

Whenever we are driving a car, we place our foot on the accelerator paddle to keep the car moving. Otherwise, the car will slow down and eventually stop moving. Same thing goes when we take a walk, we need to keep moving our muscles to make forward steps. Stop moving our muscles, and our body will be completely stationary. Make sense, right?

However, this logic is only applicable within the earth boundary. Beyond earth, this logic is absolutely invalid. The truth is, according to Newton, once an entity is in initial motion, it will remain in motion. This condition is known as inertia. Instead, a force is required to slow down or stop the motion. On earth, we have a natural force – gravity, which acts as the force of friction to halt objects from moving non-stop.

In space, as we know, it is all vacuum. Therefore, there’s almost no force to counteract the orbit movement and momentum of the earth (except for gravitational friction emitted by nearby planets, sun and moon which are extremely insignificant to cause visible effect). Just like light, it will keep traveling on and one until something major interrupts with the traveling process. (For instance, if a huge asteroid coming from an opposite direction of earth and hit us, it will slow down the speed of earth’s orbit movement. But i guess all of us will be dead by then if something as big as that hit us.)

Next question. What kicked start the movements of planets to go around the sun? What caused the earth to rotate around the sun in the first place?

The momentum was actually initiated from the rotation of the protostar. Protostar is basically the second stage of a star’s life cycle (Nebula is first) and is formed through clumps of dense gas and dust which rotate and form a disk. Hence, protostar pulls the planets within its gravity around during the formation stage and these planets danced around the big-bright-eye ever since then. See the picture below to get a rough idea.

(credit: daviddarling.info)

 

I hope i can write more about star’s life cycle in the near future … I have so many things that i wanna write, just need to find the time to articulate them out.

Written by elan85

November 18, 2007 at 7:29 pm

Posted in Astrophysics, Physics

(Yahoo! Answers) What the hell is anti-matter?

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Question: I was watching some TV show talking about the start of the universe and they were talking about anti-matter.
How can you have anti-matter? Isn’t anti-matter already matter because it’s “stuff” and it takes up space? Help me, I am confused.

My Answer: This question can only be answered effectively using analogies. Ok, try to link these 2 analogies together alright? 😉

1. I bet you know what is a magnet right? Magnetism become meaningless if it is devoid either of positive or negative charge. A magnet is a magnet because it has both positive and negative charges. Same goes for universe, to create the universe, you need both matter and anti-matter.

2. When you freeze a pile of water, heat will escape from the water and slowly turn into ice. Now, think of ice as matter and heat as anti-matter. Same goes when you put the ice under the sun, heat will take over the ice and melt it down. The best word to describe this activity is ‘reactions’.

They are not exactly very precise analogies but i hope you will get the picture of how they work. Basically, this world is a yin-yang world. Matter and anti-matter work in a harmonious way. However, the world/universe we are living at consist mainly of matters only. Therefore, some scientist believes that there’s another side of the world where it mirrors our universe, consist mainly of anti-matter, hence the Parallel World.

When matter and anti-matter meets, they will create a very strong energy (big explosions).

Best Answer chosen by Asker :

Matter is composed of particles.
Antimatter is ALSO composed of particles with exactly the same characteristics as their corresponding matter particles, but with opposite charge.

If you combine matter and antimatter, you get a huge explosion (lots of released energy) and gamma rays.

In this universe, or … at least around here, there is enough matter around that anti-matter is destroyed pretty close to instantaneously. In other places, it may be the reverse.

Written by elan85

November 9, 2007 at 5:23 pm