Jack+L

3/24/2011 Log entry #1 Information about Electronic Components, Electronic Signals, and the Use of Electricity on a Mission to Mars
aaaaaaaaaaa Analog signals go smoothly whereas digital signals jump. Digital signals can be recorded as a series of numbers whereas analog signals can’t. Analog signals are used in TV’s, VCR’s, radios, and telephones, but digital signals are used in devices like CD players. Semiconductors are useful because the conduct electricity or not conduct electricity depending on the condition. Mixing a tiny bit of another element in the semiconductor can make it conduct or not conduct electricity. This can be used by acting like switches, or increase the change in current when made into electronic components. This happens when more than one semiconductor is combined with another (a mixture of n and p semiconductors) in electronic components (called solid-state components). They are used in diodes, transistors, and integrated circuits(electronic components). A diode uses semiconductors to make electricity flow in one direction. It does this by having a p type semiconductor and an n type semiconductor. An n type semiconductor gives electrons, and a p type semiconductor accepts electrons. This means that the electricity can flow from the n type semiconductor to the p type semiconductor, but not the other way around. This turns alternating current (AC) into Direct current (DC). Alternating current goes in more than one direction, and changes direction. Direct current flows in just one direction. A transistor is a switch or an amplifier for electric current. Electronic signals can make transistors to allow current to pass through them or block the current out. Integrated circuits are made up of solid-state components. They can have millions of transistors, diodes, and other components and still be 1 mm^2 in area. This is useful because it reduces the size of devices like computers that use all of these components. If the components weren’t in integrated circuits the computers would be a lot bigger. aaaaaaa Electronics would be very useful in a mission to mars. Firstly just to take off electronics would be necessary to help with the chemical reaction involved in taking off. Then once you are in space to steer you need electronics. Also there are many probes and monitors inside the rocket that all require electronics. Also back at base they need to monitor the mission so electronics will be necessary there. Once they get to mars electronics are necessary to monitor the landing and ensure that the landing goes well. Then once they begin to search for life they need to use electronics to help them search and find evidence for life. Overall electronics play a big role in a mission to mars to search for life.

Ms. Mc - very good overview of electronic devices and how we might use them on a mission to search for life on Mars. A little more detail on the types of electronics (i.e., cameras, lasers, etc.) that we would use to explore Mars' surface would have been good. Keep up the good work! 9.5/10

4/5/2011 Log Entry #2 History of Rockets Paragraphs and Drawings
aaaaaa﻿ The Hero Engine was the first step towards making rockets. It was water that was being heated and turned into steam which travelled through pipes. The steam exited through two holes on either side of a sphere. The steam then rotated the sphere.




 * Figure 1. The Hero Engine Which was The First Big Step in Rocketry**

aaaaaaa The early Chinese also had basic rockets. The first step was gunpowder in tubes which they put in a fire to explode. Some of them might have not exploded and instead have been propelled into the air. The Chinese then started putting bamboo tubes filled with gunpowder onto arrows. The lit the tubes, and the arrows then flew because they were propelled by the tubes filled with gunpowder. The arrows helped to guide the bamboo tubes filled with gunpowder. aaaaaaaa

aaaaaaaaa Konstantin Tsiolkovsky’s contribution to modern rocketry was that he suggested using liquid fuel, and traveling to outer space. He had many good ideas, and did a lot of good research. Robert H. Goddard created the first modern rocket. He used liquid fuel, and on March 16, 1926 the first modern rocket was created. It travelled 12.5 meters into the air. It was very significant because it started the building of rockets that eventually led to space travel. As time progressed rockets got bigger and flew further.

**Figure 2. Dr. Goddard's Rocket 1926; The First Modern Rocket** aaaaaaaaaa The V-2 rocket was developed by the Germans as a missile to attack London in World War 2. By the time it arrived in the war it was too late to impact the result though. After the V-2 rocket scientests began sending sattilites into outer space. The Russians also sent a dog into outer space. NASA (National Aeronautics and Space Administration) was created to promote space travel for the good of the people. It became one of the big space organizations of the world.

Ms. Mc - Very concise and informative summary of the history of rocketry. Very good drawings too! 15/15

media type="custom" key="8964668"
__**﻿﻿Instructions for playing the rocket simulation:**__

1. Turn your sound up to about a quarter of its maximum volume. This is so that you can hear

the sound, but it's not too loud

2. Click on the green flag to start the animation.

3. Click on the red stop sign to stop the animation.

4. Click on the green flag at any time to start the animation from the beginning.

[[image:jgl_rocketphoto.JPG width="567" height="465" align="right" caption="Figure 1. Rocket Photo Labeling all of the Different Parts of the Rocket"]]
aaaaaaaaaa The rocket parts all serve different functions to help the rocket fly better. The nose cone makes it so that there is less surface area for air resistance to act upon, so the rocket can fly higher, faster, and more straightly. The body tube is necessary because it stores all of the essential components inside the rocket, and also it’s the main part of the rocket if it didn’t exist then there wouldn’t be a rocket. The recovery system is necessary, so that the rocket makes a gentle landing and isn’t damaged. It will mean that you are able to retrieve the rocket and fly it again. The recovery wadding protects the recovery system from the heat of taking off. This enables the recovery system and the rocket to be reused. The launch lug is how the rocket is attached to the launch pad, and it also helps the rocket fly straight up. The motor mount holds the motor in place inside the rocket, so that it’s secure. The fins help the rocket fly straight up. The rocket motor provides the rocket the power to fly.

//Ms. Mc: Excellent definitions! 20/02//

Log entry #5 4/16/2011 Rocket Mass Experiment Analysis and Data
aaaa The purpose of this experiment was to determine if the mass of the rocket affects the apogee (maximum height). All of the rockets masses were taken, and then the height was calculated using trigonometry. During this flight there were several forces acting upon the rocket which affected the apogee. On the launch pad all forces were equal as there was no acceleration. Acceleration is an increase in speed, a decrease in speed, or turning. The force of the launch pad was pushing up, and the force of gravity was pushing down. Both of these forces were equal, and therefore there was no movement. At lift off the engines were activated, and therefore there was an acceleration upwards. The thrust was up, but the force of gravity was down. However as there was an acceleration up the thrust was greater than the force of gravity. There was also some air resistance as air resistance opposes motion, and the motion was up so therefore air resistance was down. The rocket is now accelerating, and therefore there is an imbalance of forces. As the acceleration is up the thrust is greater than the sum of the gravity and air resistance which are both opposing the thrust. Powered flight is when the engine is still on. There is still an acceleration up. The thrust is up, and gravity is down. There is now more air resistance as it is opposing the rocket’s movement up. However as there is acceleration up the thrust must be greater than the sum of the gravity and air resistance. This means that there is an imbalance of forces which results in a movement up. When the rocket was coasting up the gravity and air resistance were acting down. The rocket was moving up due to its inertia. Inertia is that an object in motion will stay in motion, and an object at rest will stay at rest unless acted upon by an unbalanced force. The rocket is therefore moving up however it’s decreasing speed as the forces opposing it are beginning to overcome the rocket’s inertia. At the apogee for a moment all of the forces are balanced. The gravity is acting down, and the inertia is keeping the rocket up. The gravity has balanced with the inertia, and therefore as there are balanced forces the rocket stops. It was hypothesized that if the mass of the rocket is increased then the maximum height (apogee) of the rocket will decrease. This is because the higher the mass of the rocket the higher the inertia which is the resistance to change in motion. If there is a higher resistance to change in motion there will need to be more force acting upon the rocket to maintain the same height. However as the thrust is the same it will not fly as high if the mass is higher because there is a greater resistance to change in motion (it has a greater inertia). The thrust is the force that is providing the power, therefore if there is more thrust there would be a higher apogee. As the rockets that have more mass have more inertia the thrust would need to be greater to resist gravity and air resistance which are the same, and reach the same height of apogee. Lift off affects the apogee because if the rocket lifts off at a greater acceleration then the rocket can resist the force of gravity and air resistance more, and therefore have a greater inertia, and achieve a greater apogee. There would need to be more thrust at lift off to get an object that has a heavier mass to accelerate at the same rate and achieve the same apogee. However as there is more inertia the lift off will be at a slower rate which will mean in powered flight the rocket will be accelerating at a slower rate. There will be more inertia necessary for the rocket to stop, but the fact that the rocket was going slower in the first place because of the same amount of thrust was acting on a bigger mass, will make the inertia necessary for it to stop once it’s moving not as influential. Therefore if the mass of the rocket is higher there will be a lower apogee. aaaaaa The masses ranged between 41.5 grams and 46.9 grams and the apogees ranged between 62 meters and 119 meters. There was an inverse relationship as when the mass increased the apogee decreased. The hypothesis was confirmed as shown in Figure 1. The heaviest rocket had the lowest apogee as shown in Figure 1. The mass was 46.9 grams and the apogee was 62 meters which was the lowest apogee. This is confirming the inverse relationship. This was the heaviest mass, and also the lowest height. The fourth lightest flew the fifth highest. It was 45.2 grams and flew 82 meters. This is confirming the inverse relationship as those two figures are roughly proportionate for an inverse relationship. Therefore the hypothesis was confirmed. There was an outlier; it was the point where it was the lightest mass, but it had the lowest apogee. It had a mass 41.5 grams, and it had an apogee of 69 meters.This is where error may have entered the experiment. Some of the rockets were flown on different days, and therefore the weather may have influenced the results. This is because the wind may have affected the flight. The apogee depends on whether the day is calm or whether there is lots of wind. Also the angle measurements may have been off. Also the rockets may not have flown straight up which would make the trigonometry inaccurate. Also the fin placement would have determined the apogee of the rocket. The apogee wasn’t taken three times and averaged which would have led to a more accurate experiment. The apogee was only taken once. Also there wasn’t that many data points which means that there isn’t enough data to make a solid conclusion. Also there wasn’t that much variety in the mass therefore there won’t be a big difference in the apogee. The dependent variable is directly linked to the independent variable, and therefore if there isn’t much change in the independent variable then there won’t be much change in the dependent variable. Also this will mean that it’s easy for the weather and other problems to be more prominent in the result than the change in the independent variable.To solve this problem weights could have been added to the rockets. Any one of these problems, or a variety of the problems could have been the reason why the rocket that was 41.5 grams (the lightest rocket) only flew 69 meters (the lowest apogee). However overall the hypothesis that if there was a lower mass there will be a higher apogee, and if there is a higher mass there will be a lower apogee was confirmed. The data proved that there was an inverse relationship.

** 4/25/2011 Log entry #6 Answers to Questions About Astronomy ** aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aaaaa ﻿A quark is what makes up protons and neutrons. Electrons are not made up of quarks as they cannot be made smaller (they are elementary particles) There are up quarks, and down quarks. Up quarks are a charge of +2/3 and down quarks have a charge of -1/3 (as shown in Figure 1). Neutrons have two down quarks and an up quark which equals no charge as they are neutral. Protons have a charge of two up quarks and a down quark which equals a charge of positive 1. Also as shown in figure one there are strange quarks, charm quarks, top quarks, and bottom quarks. As the generation (up and down are first, charm and strange are second, and top and bottom are third) increases the mass increases, but all quarks help to make matter.

aaa The Universe is older our solar system. This is because the universe was created with the big bang (as shown in Figure 2). Then protons and neutrons started forming. Then it took 300,000 years for the temperature to cool, so that atoms could form. This was because at high temperatures atoms couldn't hold on to electrons. Our galaxy could only be created when atoms had formed. At 2 billion years the temperature had cooled enough so that gravity could form galaxies. Our galaxy formed 3 billion years after the big bang, and our solar system could not have formed before our galaxy did. Therefore the universe has to be older than our solar system.



//Ms. Mc: Very thorough answers and great pictures! 10/10//

5/5/2011 Log entry #8 A Programming Summary of Driving Course Challenge #3
aaaaaaa The purpose of Challenge #3 was to use a light or ultrasonic sensor to stop before the edge of the table which simulates stopping the robot from falling into a crater on mars by detecting when the crater is there. In challenge 3 the robot is set to go forward forever until the light sensor detects light that is greater than 23%. The robot is then set to stop and play the sound Watch Out before going off the edge of the table.

media type="file" key="jgl_robotvideo.MOV" width="300" height="300" **Video 1. A Video of the Robot Program Running**

aaaaaaa To start with the robot has a wait block, and it waits for the sound sensor in port 2 to detect sound greater than 60 decibels. This makes the robot wait to recieve a sound before starting the rest of the program. After it has detected that, there is a motor block that tells servomotor A to move up 20 degrees at 75 percent power with motor power off, which changes the motor to 100% power in case of any problem with the motor, at a constant speed, which means that it has full speed with no build up or decrease, and it tells the robot to wait for the action to be completed and to brake when it’s done. This makes the sensor that is attached to the motor go down, so that it can detect the light of the table. After it’s done that, then there is a move block which tells the robot to use servomotors B and C to go forward at 50% power straight ahead forever.This makes the robot go straight forward forever until it detects the conditions set by the next block. There is then a wait block which says for the light sensor in port 3 to generate light, and for it to wait for the light sensor in port 3 to detect when the level of light is greater than 23%.This makes the light sensor detect when the light is greater than 23% and move on to the next block after it’s detected that. After that’s been detected there is a move block that tells servomotors B and C to stop by breaking.This makes the robot stop. The robot then plays a sound block with the Watch Out sound file at 100% volume without repeating, and it tells it to wait for completion. This makes the robot play the sound Watch Out.