Illinois Junior Academy of Science - Yearbook (Urbana, IL)

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Experimental Determination of the Drag Force Ex- erted on a Model Rocket KEN CON'RA'D Glenbard East High School Lombard K- K . 3, ,gh sf,-5 - . it ff 4 , , 1 ,. i if gk , . , THE 5 HUQTA EET! MQTSSK QF BRAC The altitude, velocity and rate of acceleration of any rocket can be calculated by classical physical laws. Unfor- tunately, however, in practice the achieved results of any projectile in the atmosphere are less than the theoretical re- sults, because of air drag. I have concluded that the actual observation of a rocket in flight is the easiest way to deter- mine the drag force acting on it. To determine this drag force, three tracking systems were devised. The three sys- tems record the rocket's acceleration, maximum altitude, and the period of time it takes to reach the maximum altitude. The rocket's acceleration for any instant is recorded on a revolving cylinder by the movement of a lead weight sus- pended on a spring. From the acceleration, the actual ve- locity of that particular flight can be determined lthe area under an acceleration-time graph is velocityl and in general, the coefficient of drag can be found. If the coefficient of drag, as determined experimentally, is known for any par- ticular shape and finish of rocket, as well as the weight and specific impulse or the thrust and its duration. then the characteristics of its flight can accurately be predicted. In theory, when the drag coefficient is known, all of the actual characteristics of a perfect rocket flight can be computed exactly, such as acceleration rate, velocity, and distance traveled for an instant of the flight. However, vary- ing thrust, mechanical and human error and other factors caused the estimated results to be within 154k of the actual results. Rocketry From The Model Up GEORGE DOLAND 193 Wheeling High School Wheeling Sponsor: Edith Beniamin The purpose of my project was to show and demonstrate the many problems involved in making, designing and launch- ing rockets of all types: also I wanted to show the rockets of the present and future. I tried to get information on rocket problems and advanced rocketry. Then, with this information, I built models. Also, in addition, I designed and built my launching pad and ion rocket and demonstrated lt. Then, finally, I successfully launched a fish and brought it back alive. After this launching, I sent a second fish up twice to find out if the fish was weak from acceleration or the sudden landing. It was mainly, I felt tstill not conclusivel from the sudden landing, as the parachute did not open in the one instance, and though the fish recovered successfully it seemed weak for a longer period of time. UWB all ' 912 'Q CHRIS LUPPENS Sf. Bede Academy Peru f cell uwgig-rnlXBD lun' The flights of the Gemini spacecraft brought to light the potential power of the fuel cell. The idea of the fuel cell specifically includes an electro-chemical device that directly converts the energy of a chemical redox equation into elec- trical energy. The word directly is the key to the success of the fuel cell since the possible electrical efficiency is IOOW. Present operating fuel cells have reached a 99+W efficiency. My project concerned the development of a self-contained fuel cell power unit housed in a satellite. The experiment consisted of 3 phases: Il The actual construction of two operating oxygen- hydrogen fuel cells using nickel mesh as electrodes, platinum for the catalyst, and potassium hydroxide as the electrolyte. 23 The construction and operation of a laboratory gas supply consisting of pressurized gas tanks, whose gas was fed through two glass tubes containing water. The gas was bubbled in this manner to achieve IOOW humidity when it reached the fuel cells. 33 An experimental supply of gas obtained by traditional electrolysis of water. This unit was powered by either a rectifier or a set-up consisting of solar cells charging nickel cadmium batteries. All the above work proved profitable for the final de- sign of the satellite unit. This unit contains electrolysis apparatus, a special water tank, stack fuel cells. control panel, dielectric pumps, special silicon membranes, solar cells, nickel cadmium batteries, and various connections. The unit in theory is self-sustaining in theory, and is capable of op- erating in zero gravity. A satellite housing was designed to contain the power supply. Its approximate weight is 24 pounds, its output 24 volts D.C. at 5 - 10 volts, and its outer diameter around three feet.

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Science and Archaeology FRANK D'ARCY Northbrook Junior High KLRLRL 'WN If U Sri' Carbon 14 is created when a nitrogen atom is struck by a cosmic ray. The result is Carbon 14. Carbon 14 is radioactive, that is, it gives off beta particles. The Carbon 14 is absorbed by all life. When an organism dies it loses Carbon 14 at a steady rate, in 5,568 years one half is left, in 11,136 years one fourth, etc. By measuring the Carbon 14 we know how old an object is. In pottery, radioactive matter such as uranium thorium and potassium give out alpha, beta and gamma rays. The rays knock stable atom's electrons out of their natural orbit. These electrons are trapped in the clay and when heated to 5000 C. they are forced back into their normal orbits. When this happens each electron emits a photon of light. This light is measured and the more light the older the object is. This is known as thermoluminescence. In clay there are particles that are magnitized. They point all ways and cancel each other out. When heated to 600 C. they tend to align themselves along with the magnetic poles of that day. Since magnetic poles shift, to find out how old an object is, all we have to do is find the way the particles in the clay point and look up the date when the poles were in that position, this is known as archaeomag- netism. In bones fluorine and uranium is absorbed when water seeps through to the bones. At the same time nitrogen is lost through protein decay. Because the amount of fluorine and uranium gained and the amount of nitrogen lost depends on the place and conditions in which the bones were found, scientists have come up with an average for normal condition - this is the fluorine process. There are two main types of aerial photographs: vertical and oblique. Vertical are the results of crop growth. Over trenches plants grow bigger and more luxurant, and so have a darker color. Over walls the plant growth is stunted and the plant color is lighter. Oblique photos are the results of shadows. Over buried walls slight hills are formed. These cast shadows. Four Cultures Ai' Yankeetown ELLEN MARTIN Carl Sandburg Junior High The theory that four consecutive cultures of four dif- ferent groups of Indians had occupied the Yankeetown area at different times could only be proved by Archaeological excavation. The idea was that the four following cultures had at one time existed here: A. Archaic culture - wandering food gathering and hunters: had primitive tools: no pottery. B. Baumer culture -- an early woodland culture who were food gatherers and storers, hunters with more refined stone tools and pottery. C. Middle Woodland -- more advanced cultivators of foods: hunters with stone toolsg some copper and food gath- erers and storers, D. Late Woodland - advanced cultivators and hunters: more refined tools 3 some metal toolsg pottery of more durable nature. Since I am a member of the Chicago Archaeological Society, I was invited, along with my family to attend Dr. Emily Blassingham's 'dig' at Yankeetown and observe the work going on to prove the above theory. The evidence uncovered pointed to the affirmation of the theory, the dig was fruitful, and there was significant evidence that there had, indeed, been four cultures at Yan- keetown. Dr. Blassingham hopes to return to the area for further study, and I hope to be able to go and participate, agam.