Michael+D


 * Prompt 1: **

3/23/2011


 * The Facts and Importance of Electronic Devices and Components.**

Analog signals are different from digital signals because digital signals don’t change smoothly, but rather in jumps or steps. Digital signals are 1’s and 0’s, and an analog signal is all the numbers in between. Semiconductors are useful to electrical devices because they can supply a certain amount of current, rather than just all or nothing, which is what insulators and conductors do. Diodes, transistors, and integrated circuits control the flow of electricity in a circuit. A diode can convert AC to DC because it is polarized. Transistors amplify signals in a circuit and can act as a switch. An integrated circuit is a single chip of semiconductor and many transistors and diodes, fitting many transistors and diodes in the space only one or two normally sized ones would fit in.

Electrical devices are important in exploring Mars because they can survive in the conditions on Mars, and it would be much harder to send humans there. People would need food, water, shelter, and many other things to survive on this foreign planet, as well as some other possible complications. Robots can take energy from the sun, which keeps them going until the sun goes away. This is also safer, even though you could probably get more information with an actual human there. On the whole, it is easier, safer, and has been done before. It is a better route to go with the technology that we have now.

//Ms. Mc: good summary of electronics. You present a good argument for why we should use rovers instead of humans, however, the question was how would we use electronic devices on our mission to mars. Specific electronic devices we might use include: cameras, soil analyzers, communication systems, computers, navigation systems, etc. 8.5/10//

Prompt 2 March 30, 2011 The Evolution of Rocketry and Space Travel

Rockets began as accidental bamboo sticks with gunpowder flying up in the air, and have evolved into large spacecraft flying to different plants and worlds. The first invention with rocketry principles was an aelopile, a steam propelled sphere mounted on a water kettle, making it spin. The first true rocket ever created were the Chinese fire arrows, arrows with the first ever rockets mounted on them. The stick guided the rocket through the air, and the rocket whizzed towards the Chinese's enemy at that time, the Mongols. After this Chinese invention, people around the world began exploring this new idea of the rocket. Konstantin Tsiolkovsky, now known as the Father of Modern Astronautics, and a Russian schoolteacher, was the first person to suggest using rockets to go to space, using liquid fuel. Robert H. Goddard began to conduct experiments to try to make a liquid fueled rocket. He developed a gyroscope system for flight control, payload compartment for scientific instruments, and parachute recovery systems to return the rockets and instruments. In Germany, they had invented the V-2 rockets, which burned liquid oxygen and alcohol and were devastating weapons that were used in World War II against London. The Americans and Soviets won this war, however, and took possession of the remaining rockets. Many of the German rocket scientists came to the USA and the Soviet Union, and created ballistic missiles and rocketry weapons. Then they began realizing the potential of these rockets, creating the rush to get to space. Sputnik I was the first rocket to reach space. This satellite was created by the Soviet Union. The Russians then launched another satellite a month later, carrying a dog. A few months later, the first American satellite was launched, called Explorer I. Then, NASA was created, followed by our modern astronautics and space exploration, including weather forecast, brilliant pictures, and foreign planets.

Figure 1. The Chinese Fire-Arrow.

Figure 2. Modern Rocket. // Ms. Mc: Excellent summary of rocketry and drawings! 15/15 //

April 4, 2011 Entry #3 Rocket Flight Stages Simulation

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Turn up your sound and click on the green flag to start the simulation if it does not start automatically. Press the red stop sign to stop the simulation.

Prompt #4 April 12, 2011 Rocket Parts

Figure 1.

The nose cone decreases air resistance with streamlines. The body tube is the body of the rocket, the main part of the structure. The recovery system keeps the rocket intact when it returns for repeated use. The recovery wadding protects the recovery system from ejection gases. The launch lug helps the rocket get a straight liftoff by guiding

//Ms. Mc: Good start but you only defined 5 of the 8 parts and didn't finish your sentence for the launch lug (-3.5). You also misspelled Body Tube in your labels (-1/2). Please read over your work before you post it. 16/20//

** Prompt #5 ** ** 4/18/11 ** **Rocket Launch Lab Write-Up**

The purpose of this experiment was to find if the mass of a rocket affected its apogee height. Seven rockets with different masses were launched, and their apogee height was found using trigonometry. A rocket’s flight consists of six phases, which are ignition, liftoff, coasting, apogee, ejection, and landing. The rockets used in this experiment only went through ignition, liftoff, coasting, and apogee. During ignition, the engines start, preparing for liftoff. The engine is not making a force yet, and the force of the launch pad and gravity are equal, so the rocket is not moving. Then the engine begins to create force, and the rocket lifts off. During liftoff, the force of the thrust overcomes the force of gravity and minimal air resistance. This continues until coasting, when the rocket continues its flight with inertia, which is overcoming gravity. When the rocket loses its inertia, it arches over. This is apogee. It was hypothesized that the greater the mass then the lower the apogee will be because more force will be needed to get it to that height, and the same force is being applied to each rocket.

The masses of the rockets varied from 42.5 g to 45.4 g (as seen in Graph 1). The apogee heights ranged from 61 m to 93 m (as seen in Graph 1). The relationship between the mass of the rockets and the apogee heights was direct. This proved the hypothesis wrong, as the apogee height increased (as seen in Graph 1). However, once the rocket mass reached 44.5 g, the apogee height began to decrease. An error might have occurred in the measurement with the angles used to calculate the apogee height, as different people measured each angle. This would change the apogee height.

Prompt #6 4/25/11 2 of the 4 Questions

What is a quark? What types of quarks are there?

Quarks are very small particles of matter that combine to form hadrons. The most stable hadrons are protons and electrons (As Seen in Figure 1). There are six types, or flavors of quarks: up, down, charm, strange, top, and bottom. Up and down quarks are the most stable and most common in the universe.



What is a galaxy? How are they formed?
A galaxy is a system of stars and stellar remnants, which are held by gravity. Galaxies formed when, after the Big Bang, larger masses were formed. This created more matter to be attracted to the large masses, creating a galaxy (As Seen in Figure 2).



Ms. Mc: Good answers and pictures but you need to add a little more detail (-1). Your captions need more detail as well. In fact, figure 1 is not a proton or an electron (-1). Your entry title also should be more descriptive so the reader knows what is coming. With a little more effort, you would be getting 100%. 8/10

** Log Entry #8 ** ** May 5, 2011 ** ** Instructor Challenge #1: Driving Course Programming Code ** In this challenge, the robot had to drive along tape, first driving forward, then turning right, driving forward again, completing a left point turn, driving backwards, complete two complete circles (720 degree spin), robot displays a smiley and plays the applause sound.

Block 1 – a movement block that makes the robot move forward for 3.65 rotations by telling it to activate servomotors B and C so it moves forwards for 3.65 rotations at 75% power and then brakes. Block 2 – a movement block that makes the robot turn right 90 degrees by telling it to activate servomotors B and C so it moves right for 175 degrees at 75% power and then brakes. Block 3 – a movement block that makes the robot move forward for 1.827 rotations by telling it to activate servomotors B and C so it moves forwards for 1.827 rotations at 75% power and then brakes. Block 4 – a movement block that makes the robot to turn left 90 degrees by telling it to activate servomotors B and C so it moves left for 175 degrees at 75% power and then brakes. Block 5 – a movement block that makes makes the robot move backwards for 1.415 rotations by telling it to activate servomotors B and C so it moves backwards for 1.415 rotations at 75% power and then brakes. Block 6 – a movement block that makes the robot turn right 720 degrees by telling it to activate servomotors B and C so it moves right for 1400 degrees at 75% power and then brakes. Block 7 – a wait for time block that tells the robot to wait and do nothing for 1 second Block 8 – a display block that tells the robot to display Smile 01. Block 9 – a sound block that tells the robot to play the sound file Applause at 100 volume and then wait for completion.