Tuesday, May 3, 2016

49th Annual Summer School Day 7:(02-05-2016) Physics Olympiad Experiments



On 2nd May 2, 2016 in the Summer School of Science we had the privilege to try out the experiments on various aspects of physics prescribed by the International Olympiad for Science under the guidance of professors like Sreedhar Swamy Sir, Kamala Madam and many others.
The list of the experiments that we tried out included:
1. The calculation of Surface Tension and Viscosity of Water.
2. The calculation of Acceleration due to Gravity
3. Diffraction
1. Calculation of surface tension and viscosity of   water:
 
Aim: To use diffraction of a laser on the water surface to determine surface tension.
In this experiment we use the diffraction pattern emitted by the vibrating water surface to calculate the surface tension of water.
Firstly we determine theta by using trigonometry i.e. we move the light sensor to different markings and then we note down X and Y component then plot a graph and find the slope which is theta.

Calculation of SurfaceTension                                                                       
                     
For calculating the surface tension we use the sound emitting device to produce desired and controlled vibrations in the water surface. Then we obtain a series of diffracted laser points on the light detector then we need to measure the distance between the 2nd order points, then we repeat the same from a frequency of 60 to 180 Hz with an interval of 10 Hz and then plot a graph of f v/s x1. We then calculate slope1. Then we plot another graph of f2 v/s  x13. Then we calculate slope2. Must calculate surface tension using   the given formula.
                                  
 Calculation of Viscosity:

 
For calculating the viscosity of water we must first set the frequency of the sound to 100Hz. We must then set the vibrator marker at 8cm. We must adjust the light sensors using vernier calipers to the 1st order. We must adjust the amplitude such that the lux meter shows a reading of 100 and then note down the Vrms. Then we find out the natural log of Vrms. We must plot a Vrms v/s S and calculate slope3. Then we must calculate Delta and Viscosity.
                  
2. Calculation of time period of a simple pendulum 
 First we need to suspend a metallic bob from a support with its length as 100cm. Then we need to take number of oscillations per minute. After taking down the oscillations we must find out the frequency of the pendulum. Then repeat the same for lengths of 50 and 25cm. Since time period is the reciprocal of frequency
3. Diffraction
A  Brief Introduction about Diffraction:
The bending of waves around the obstacles.  

Diffraction takes place with sound waves, with electromagnetic radiation, such as light, x-rays, and gamma rays and with small moving particles such as atoms, neutrons, and electrons, which show wave like properties.

In light diffraction is the slight bending of light as it passes around the edge of the object. The amount of bending depends on the relative size of the wavelength of light to the size of opening. If the opening is much larger than the light’s wavelength, the bending will be almost unnoticeable.
Applications of diffraction


The effects of diffraction are often seen in everyday life. The most striking examples of diffraction are those that involve light; for example, the closely spaced tracks on CD or DVD acts as a diffraction grating to form the familiar rainbow pattern seen when looking at the disk. The principle can be extended to engineering a grating with a structure such that it will produce any diffraction pattern desired; the hologram on a credit card is also one of the examples.

Today in the lab we studied about LASER DIFFRACTION ANALYSIS also known as LASER SPECTROSCOPY, … this is a technology that utilizes diffraction patterns of  a laser beam passed through any object ranging from nanometers to millimeters in size, to quickly measure geometrical dimensions of a particle .

The apparatus required for this experiment is:  a red laser light which is attached to a wooden platform.  Then we need a lens where the sample is attached (here we studied the structure of spring – or the helical structure).  Then we need 2 reflectors, a black surface which receives the laser light after reflection, and a particular X shape is formed on the black surface.  Then we require a sample holder, a wooden platform, a direct current source, clips, a mirror and a plane white sheet
Procedure or the process of the LASER BEAM ANALYSIS
 
First we switch on the direct current source from where the laser will get power, the laser light is lit up. We were asked to make the reflected ray to go back to the laser i.e. we will have 2 points of the laser on the white paper which will be clipped on the black surface. So to make the rays meet we will have to adjust the black screen, or even sometime the laser. If the apparatus is correct we get an X shaped pattern, and if we observe keenly we get to see small spring shaped structures on the white paper. Then we had to mark the distance between the two consecutive springs using a pen pencil, we were also asked to mark the center of the laser beam and the small area around it. Then Y.C.Kamala madam took us through a little bit of trigonometry. 
i.e. sin theta = opposite side /hypotenuse,  
cos theta   = adjacent side/hypotenuse,  
tan theta  = perpendicular/base.  

Based on this basic formula of trigonometry the whole experiment was dependent. So we were asked to measure 2x distance (i.e. the distance between the center point, the upper and the lower widths this would give us 2x), my group took 7 measurements. Then we were asked to construct an order v/s width graph. The slope formula is: measurement on y axis * 2/ measurement of x axis, my team got the value as 2.35.  Then madam told us to measure the thickness of the spring using the formula 2*  (value 635*10-9) * 277/ slope value. As it’s in m form we have to convert it into mm form.  So the denominator is like this slope * 10-2.  Our team got the value as 0.1496* 10– 3m. Then after finding the thickness we have to find the angle in the curve of the spring.  So to find it we have the formula tan theta.  Tan theta = perpendicular / base.  Our team got the answer as 22.29 degrees. So there the experiment ends. In this experiment lot of mathematics, physics and trigonometry is used. 

Sunday, May 1, 2016

49th Annual Summer School Day 6:(30-04-2016) Speaker:Sumangala Mummigatti Topic: Science Communication



Report 1:

Name : D. Raghavi
Group :  6


 I am Raghavi , from group 6 of the summer school .My report is about science communication session at the school, conducted by Mrs. Sumangala Mummigatti.
This day all of us got a chance to explore our creative talent. This chance was given by Sumangala Mummigatti ma’am. Everyone wanted to showcase their talent… so, they got a path to it.

At first ma’am gave us an introduction to science communication, later she continued it with examples. Then we came to the practical session where we were given tasks .We were divided into four groups  .It was our choice to choose anyone according to our capability.. We had an option to write an article, or a poem, or a drama , or a feature..

From my side I chose to write an article. My concept was to write about “Is there life on mars ? What supports life on earth ?”  I had prepared well before about it . So, I didn’t find it so difficult on the day. After everyone wrote they collected  the pages and ma'am read some of it. Later after a keen observation ma’am selected few articles, few poems and dramas. The first one was about ants. The next was a poem about light, with a good rhyming .Then a drama with the concept of garbage . It was good and realistic. Then was article about constellations .At last we had a story about communication. All of  the programs were good and had a message in it.

So, I thank everyone who supported us in this activity.

Report 2:

Name: Nagasubramanya.C


I am Nagasubramanya ,from group 6.

I opted for a story and performed the activity with my group. They had given us a time limit of hour . Our drama was about communication . Title  of our drama was Need for speed . Then my classmates supported a lot to me to prepare the story .ma’am selected  the best ones and asked them to read it.all of the programs had a good outcome and had a proper moral in it.


Saturday, April 30, 2016

49th Annual Summer School day 5:(29-04-2016): Talk by Prof: MRN Murthy, IISc. Topic: "The Wonderful living"


Today was a amazing and interesting lecture based on our wonderful living world. Professor MRN Murthy explained today’s students about the living universe.It was a mesmerizing topic and presentation which attracted all the students present.We learnt a lot of unique facts and tried to acquire knowledge as much as possible by Prof. M.R.N Murthy on the topic The Living World.


The cosmos(the universe) and the brain are the wondering subjects and have some sort of connection in them.


Cosmos- This is far as anything on Earth can see. The age of the universe is 14 billion years, so in theory we are unable to observe anything further than 14 billion light-years away. Due to the expansion of space, these objects are now around 46 billion light years away — the limit of the observable universe. In fact, the photons in the cosmic microwave background have travelled a cool 45 billion light years to get here. That makes the visible universe some 90 billion light years across. That's big but the universe is almost certainly much bigger.


 The brain- The human brain has been called the most complex object in the known universe, and in many ways it's the final frontier of science. A hundred billion neurons, close to a quadrillion connections between them, and we don't even fully understand a single cell. 
The two wonders of the world is cosmos and the brain. The small muscle tissue present in living organisms is really an gift to us. It is a mini super computer which has the thirst to know about the amazing wonders.

The story of Earth is an epic filled with crises, catastrophes, and remarkable, repeated change. Earth traces its origin to simple atoms that were created in the big bang, transformed into heavy elements in stellar explosions, and then forged into a planet inside the nebula that gave birth to the solar system. Like many other planets, Earth went through phases of melting, volcanism, and bombardment by asteroids. But only on Earth did events lead to a flourishing biosphere—life. And once life was established, it drove the evolution of our planet in startling new directions. Rocks that date to the early stages of the formation of the solar system arrive on our planet all the time. They are chondrite meteorites, which are 4.567 billion years old, older than Earth itself.


Green Earth: The green of photosynthetic life is the most visible sign of the living world.



We also learnt some interesting facts about the celestial body like:



Sun is a celestial body which is 150,000,000 away from sun and 5000 years old and takes 8 to 9 min to reach Earth.

Comet is a celestial body which is also believed as granting wishes but if collides with Earth it can cause a catastrophe and it consists of solid carbon-dioxide and ice.

Important fact- 12 November 2014


ESA’s Rosetta mission has soft-landed its Philae probe on a comet, the first time in history that such an extraordinary feat has been achieved.


“Rosetta is trying to answer the very big questions about the history of our Solar System. What were the conditions like at its infancy and how did it evolve? What role did comets play in this evolution? How do comets work?” 


Evolution of gases


After loss of the hydrogen, helium and other hydrogen-containing gases from early Earth due to the Sun's radiation, primitive Earth was devoid of an atmosphere. The first atmosphere was formed by outgassing of gases trapped in the interior of the early Earth, which still goes on today in volcanoes. 


Life started to have a major impact on the environment once photosynthetic organisms evolved. These organisms, blue-green algae  fed off atmospheric carbon dioxide and converted much of it into marine sediments consisting of the shells of sea creatures. While photosynthetic life reduced the carbon dioxide content of the atmosphere, it also started to produce oxygen. Once oxygen had been produced, ultraviolet light split the molecules, producing the ozone UV shield as a by-product. Only at this point did life move out of the oceans and respiration evolved.


Present challenge-the arising crisis of the present day is the shortage of power.



Newtons law of  inertia-


Uranium which divides the nucleolus on its own without any external force and iodine which goes on decreasing for a fortnight without any external force.


Invention of microscope  is great contribution


We also learnt that there were many microscopes designed at the beginning to observe minute things which were not that magnified. Then the fact that electrons also emit light gave rise to electrone microscope which helped in observing minute things which were far from the observation of normal microscope. Then as time went along there were


X-ray which helped in determining the structure of the molecule.


  Some electron microscopes can magnify specimens up to 2 million times, while the best light microscopes are limited to magnifications of 2000 times. Both electron and light microscopes have resolution limitations, imposed by their wavelength.


 Some electron microscopes can magnify specimens up to 2 million times, while the best light microscopes are limited to magnifications of 2000 times. Both electron and light microscopes have resolution limitations, imposed by their wavelength.


DNA is the essential component and its unique from one another.there’s a sequence structure function relationship.


 


Quantum mechanics-


Rate of radioactive decay depends on the number of nuclei present.


 


QUESTIONNAIRE SESSION-





o   IS RAMAYANA THE ENSCRIPTURE TRUE IN ALL THE FACTS?

o   Some facts are not  true in all aspects. Like that of pushpaka vimana.



o   Some scientists are against “theory of evolution”?

o   Theory of evolution is true . its better to believe the fact.



o   Researches are  going on based on anti-aging?

o   Aging is a lively process in all living organisms. We can stop aging but its not necessary based on today’s situation



o   If all the honeybees die , humans will also die in the next four years. Is it true?

o   No its not, it wont affect the diversity of human beings.



o   They say there’s only possible of survival of the fittest.

o   Every living organisms has consciousness. It has super inherent powers .