ATOMIC DEBATE - SETTLED
Albert Einstein saw the value of the theory of Statistical Mechanics same as gold. He understood the mathematical value of this theory and even commented on it:
“Absolutely Magnificent”
Brownian motion:
Many believed that these players were very small atoms. The idea was dropped because of the less quantity of the supporters of this idea.
The atomic debate continued.
Einstein Got The Solution:
Einstein was the first one to conceive an efficient way of analyzing the motion or ‘erratic’ motion of the pollen grain. He studied the result of many collision rather than studying every single one of them. It was much easier and more precise to measure how far an average grain travel in an extended time, such as one minute during which many collisions occur.
To extract a good theory from his hypothesis he derived predictions. He published a Diffusion equation in the year 1905 that predicts the average distance a pollen grain travels through a liquid in a given time. The exact equation is much more complex than given in this post.
The predicted distance depended on the properties of the pollen grain and the properties of the liquid. They are really easy to measure. The distance also depends on the number of atoms in a given volume of the liquid. Einstein’s equation helped to calculate the number of atoms in a specific volume with the help of the average distance pollen grains travel and the properties of the pollen and the liquid.
From the Diffusion Equation average distance travelled by the pollen grain can be calculated with these four parameters: grain size, time, the liquid’s temperature and the liquid’s viscosity.
For example, if the temperature is increased 6% then the average distance travelled will increase by 3%. If the grain’s size is decreased by 4% then it will move 2% farther. It predicted a lot of things.
The Diffusion equation: d2 = (yT/ru)*t/n
Increasing the value of small t allows the pollen grain to travel farther. The bigger the value of N, the smaller will be the impact on the pollen grains.
If the pollen grain moved along a straight line or straight path with a constant velocity v for time t then it will travel a distance of d = v*t. But, the problem was that the grain was constantly changing direction, moving in an erratic motion. Einstein wanted to find out the average distance travelled by the pollen grain.
This problem had been coined the name “The Drunken Sailor” or “Random Walk”. A drunken sailor falls down, gets up, takes
a step in a random direction and falls down again. It was found out by Einstein that the square of the distance is proportional to time. It takes 4 times as long to travel twice as far when each step is taken in a random direction.
All these predictions were proven true in careful experiments by French physicist Jean Baptiste Perrin, who received 1926 Nobel Price for this work.
At last, the 80 years old mystery of Brownian motion and 2500 years old atomic debate were finally settled. Thanks to Albert Einstein.
I welcome your comments, feedbacks, questions or suggestions. You can start a conversation below or contact me directly at:
OR
2 comments
Keep Up The Good Work
ReplyDeleteThank you
ReplyDelete