Showing posts with label Physics. Show all posts
Showing posts with label Physics. Show all posts

Wave or Particle?

Posted by Sameer on 12:43 AM
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Here's a video,I found on YouTube. Why did 'Quantum Mechanics' take birth when the world had the 'Classical Mechanics'? The following video gives the answer.


You see,the electrons are particles, however they behave like waves. These are some of the questions which the 'Classical mechanics' couldn't answer. So came the 'QUANTUM MECHANICS'.


Let me put some light on the history of Quantum mechanics.

Developmental milestones:

1. It started with Huygens' wave theory of light. Huygens was the one to propose that Light behaves like a wave. He tried to explain phenomenon of reflection,refraction with his theory, but couldn't give satisfactory explanations. We all know that, Light does not need any medium like air,water for it's propagation. It's due to this fact, we can receive sunlight even though there is void between the sun and the earth. However, Huygens assumed a invisible medium to be present everywhere,called as 'Luminiferous ether'. He said that this medium is essential for propagation of light. Many scientists tried to locate it, but their attempts were in vain.

2.Then came,one of the most famous men in the world, Isaac Newton. He proposed the 'corpuscular theory of light'. It said that, the light consists of small,little particles called 'corpuscles'. With this theory he could easily explain phenomenon of reflection. Somehow, he also managed to explain Refraction, the propagation of light through the lens etc.

3.In the early 1800, Young and Fresnel put forward their experiments to support the Huygens' wave theory of light. Young's double slit experiment was the first to discover that the light travels as transverse waves but not longitudinal waves. He observed that when the light is passed through two slits, a pattern containing alternate bright and dark bands is observed on the screen. This pattern is called as 'Interference pattern'.

4. In the late 1800, James Maxwell explained light as the propagation of electromagnetic waves using some mathematics. This theory was accepted widely.

5.In 1901, Max Plank proposed that light propagates as small packets of energy called as 'Quanta'. The theory was carried forward by the person of century, 'Albert Einstein'. However, Einstein preferred calling 'Quantum' as 'Photons'. He explained the phenomenon of photoelectric effect using theory of photons for which he received the 'noble prize' in physics in 1921. Who switches off the lamp posts on highways in the morning? Why can't a bugler break in a house so easily,nowadays? How do we measure intensity of light? It is all possible because of this one man and the photoelectric effect.

6.De Broglie's Hypothesis: Mr.De Broglie claimed that not just the light, but all matter behaves as a particle as well as waves.He called them 'matter waves'. He found a relationship between momentum of photon and the wavelength. This guy also was awarded a noble prize in physics in 1929.

So, "Is light a wave or a particle?” Perhaps it depends on the type of experiment you do,as you can see above.

-reference Wikipedia




Note: If you find any mistake in information or logic written above, Please let me know. Suggestions are welcome.

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Obulis: The Physics game

Posted by Sameer on 3:25 AM
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NOTE: This post is designed based on the videos. So please do watch videos before reading to their descriptions.

Here's another fabulous physics game. This one is based on one of the most interesting concepts in physics, Kinetics of particles(Dynamics). You must have seen on YouTube, mechanisms in which the narrator releases a ball or slightly pushes a plate and then everything happens on its own. This game is kind of similar to such mechanisms. In each level, our target is to put the coloured balls in corresponding vessels.


Oscillations, Impacts, Work Energy Principle are some the frequently encountered phenomena in this game. Following videos explain some of them:




The red ball takes the cover of two gray balls. Unfortunately, I'm a bit smarter. I kicked butts of two gray balls and eventually the red ball got one on it's own. Also observe the position of the ball when I cut the rope. It's the center!

Logic:(i) The velocity of oscillating particle is maximum at the center and minimum at the ends of it's path.As a result, when I release the ball when it is at the center of its path, it strikes the gray one with maximum velocity.

(ii) When you strike a ball with another ball in rest, the latter is set into the motion. This happens because of the concept called as 'Inelastic collision'. The part of kinetic energy of the first ball is transmitted to the second ball, due to which it starts moving. In the above case, the impact of oscillating gray ball on the stationary one, transmits the kinetic energy of former to the latter. This energy travels through and eventually reaches the red ball. As a result the red ball is set into the motion. Whenever two bodies collide, such that there is loss of kinetic energy, then such a collsion is called as Inelastic collision.





This case is quite similar to previous one. But, note that the height up to which the blue ball reaches is equal to the height achieved by the gray one.

Logic: The concept is, THE LAW OF CONSERVATION OF MOMENTUM.

Momentum is the product of mass of the particle and it's velocity (mv). Let me explain this in simple words. You may survive if you get hit by a car traveling at 20 m/s. However, You are doomed if you get hit by a train traveling at 2m/s.
The reason is, the mass of the train is very large as compared to that of the car. Hence the product (m*v) i.e. the momentum for train is huge even if the speed of train is less.

Anyways, The law states that,

(m1v1)i+(m2v2)i=(m1v1)f+(m2v2)f

[m1 and m2=> masses of colliding particles.

v1 and v2=>velocities of colliding particles.

'i'=>Initial values

'f'=>Final values]


If blue and gray balls have same mass then m1=m2.

Blue ball is initially at rest. (v2)i=0

After collision, gray balls remains stationary. (v1)f=0


therefore, (v2)f=(v1)i. Thus,velocity of blue ball after collision is equal to the velocity of gray ball before collision.


Following are some more cool mechanisms implemented in the game.




I'm sure you must have liked this one as well. I think, these games make physics more interesting to learn and to teach.:)



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WORLD OF GOO: An Ultimate Physics game

Posted by Sameer on 3:58 AM
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NOTE: This post is designed based on the videos. So please do watch videos before reading to their descriptions.

Goo? What is Goo? Is the game all about 'shit'?
I thought the same when I heard about this game. But when I played it, I found it tastier than anything.

World of Goo is a puzzle game with a very strong emphasis on PHYSICS by 2D boy. Design,story,art and music are by Kyle Gabler. The game is programmed and produced by Ron Carmel. Here are some reasons why you should play this game...


Concept :

This game picks some of the most simple but beautiful concepts,theories of physics.

In each stage, our target is to reach upto the escape pipe. In doing so,we encounter various phenomena in mechanics like Gravitation, Oscillations, Projectile motion, Buoyanct force exerted by liquid, Resonance, Circular motion, Archimedes' principle etc. Tackling and clearing each problem is really a fun and we get to learn a lot from it. The game is simple,small but needs brain.



Let me introduce to you some nice concepts of physics.

This is one of the initial stages in World of Goo. Two strong gates prevent Goo balls from reaching their goal. But I use round round baloons to open them and Goo balls fly high up in the sky.





The escape pipe is situated well above the ground. So goo Balls had to make a huge tower to reach their goal. It was OK at start, however as the tower grew tall, it's top started oscillating due to motion and weight of Goo balls. To prevent the tower from collapsing, I used whistle(look at the cursor) to pull Goo balls to the lower part of the tower. As a result, the mass of Goo balls got concentrated in the lower part and upper part became stable, thus allowing me to build further.
Logic:Considering damping is present, Amplitude of oscillation of pendulum depends on mass.
If mass is less,Amplitude is small. Since the mass at the top was reduced, amplitude decreased.



The escape pipe is at a height above the water surface. In order to take Goo balls there, I used the concept of Buoyanct force exerted by liquid. The yellow Goo ball took others well below the water surface and then realesed it's hold to sprang out of the water.Whoooooooosh!!!!
Logic:When a object is submerged in a fluid (completely or partially), there exits an upward force on the object that is equal to the weight of the fluid that is displaced by the object. This is what Archimedes s aid when he got old.




Goo balls were trying to dispose that 'undelete' block in the water. Their plan was to jump on that rope, swing the rope and when it comes exactly below the fire, jump through the fire to destroy the structure. However, due to some reason,they couldn't execute the plan. I helped them and the mission was accomplished. What was that mistake they have been doing? They were jumping on the rope while it was coming towards them.
Logic: Logic is simple. When a body is hit by an another body travelling in opposite direction, velocity of former decreases and if directions are same, then it increases. If Goo balls are thrown on the rope, when it is heading towards them, AMPLITUDE OF OSCILLATIONS of rope will obviously decrease. Therefore,they must be thrown,when rope is going away from them,so that bottom end of rope comes exactly below the fire.




Yooohooo! Goo balls experiencing NEWTON's gravitation. Goo balls jump into the space to reach their goal.
Logic: Everyone knows! Sir Isaac Newton was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian and one of the most influential men in human history. He proposed the law of gravitation. It states that, any two objects in universe exert gravitational force of attraction on each other.



So, You should play this masterpiece.



No wonder, this game receives the title of 'THE BEST PUZZLE GAME OF YEAR 08'.

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