Kevin+W

Electronics and Computers
=== Analog signals very smoothly while digital signals jump from number to number instantly. That is where analog and digital clocks come from. Semiconductors are useful because you can control their electrical conductivity by adding impurities, or other elements, which can be used to control how and when the semiconductors start conducting. Diodes are used so the current only flows one way. Transistors are used to either block or amplify the current. Integrated circuits can contain millions of diodes and transistors. These circuits are used to affect the flow of the current. ===

If you were able to send humans to Mars; than electronic devices would be especially useful. You could use the electronic devices to stay in communication with the base on Earth. You could also transmit signals that could show the power levels on the spaceship, or the temperature or air levels on Mars. Also, you need electronic devices to control the oxygen in the spacesuit, or the power levels in the spaceship. I’m pretty sure the astronauts will want to have enough power to head back to Earth. If a robot were sent to Mars; than electronic devices would be even more crucial to make sure the robot is working. Also so the robot can keep in contact with home base. Electronic devices are so crucial for space exploration that all of this would be impossible without it.

//Ms. Mc: Good overview of electronic components. Since we currently aren't sending humans to Mars, it would have been beneficial to list electronic devices that would be used on non-manned missions such as computers, navigational systems, temperature control systems, soil analysis equipment, camaras, etc. Please include your log entry # in your title. 9/10//

History of Rockets
=== ﻿The Hero Engine shows how a rocket needs a thrust by pushing steam one way. This leads to an equal and opposite reaction that we use today to thrust a rocket. A rocket-like device called an aeolipile was the first to employ the principles essential to rocket flight. The Chinese began with gunpowder filled tubes. They attached bamboo tubes to arrows and launched them with a bow. They realized that the tubes could propel themselves with the escaping air. During the battle with the Mongols in 1232, the Chinese repelled the Mongols with arrows of flying fire. A tube which was capped at one end, contained gunpowder. When the powder was ignited it could propel the tube by sending fire and and smoke out of the open end of the tube. All rockets at that point were either used for warfare or fireworks. The early rocket discoveries spread to Europe in th 13th to 15th centuries. From this a variety of items were invented, such as bazookas by Jean Froissart and torpedoes by Joanes de Fontana. Konstantin Tsiolkovsky proposed using rockets for space exploration, and liquid propellants. ===

[[image:khw_flamingarrow.jpg width="306" height="192"]]
Figure 1: Arrow of Flying Fire

Modern Rocketry was started by a man names Robert Goddard. He was the first person to create a working liquid propellant rocket. He sparked a revolution in the 20th century that would lead to human space exploration. Goddard was named the father of modern rocketry. After World War II ended in 1945, two powers, the US and the Soviet Union realized the potential of rockets as military weapons. Both countries started experimental programs. The Soviet Union shocked the world in 1957 as they sent the first satellite into space, Sputnik I. They later sent a dog named Laika into space, this dog survived 7 days in space before being put down due to lack of oxygen. A few months after Sputnik, the US sent their first craft, Explorer I, into space. Soon people and more machines were launched into space. Rockets have given us a bigger opportunity than before to explore everything we can possibly explore. Figure 2: Sputnik I

//Ms. Mc: Good summary of the history of rocketry. The contributions of German scientistis to modern rocketry is missing from your second paragraph. I like how your diagrams illustrated some of your main points. Good job, overall. Please remember to put the entry # in your title. 14/15//

Rocket Simulation
media type="custom" key="8956608"

Instructions: 1. Turn on sound 2. Click on Green Flag 3. Enjoy! _

[[image:khw_rocket.JPG height="421" caption="Figure 1: Labeled Rocket"]]
This rocket shows many parts needed in a rocket. The nose cone at the top is used to guide airflow. The big body tube is what holds the entire structure together and prevents it from collapsing. The recovery system, which is inside the body tube allows a parachute to pop out once the rocket reaches its apogee. This allows the rocket to mean intact when floating down so it can be reused. The recovery wadding, which is also inside the body tube keeps the rocket motor from heating up and burning the recovery system. This is used to keep the recovery system from getting destroyed. The launch lug is a small tube that is used to guide the rocket off the launch pad safely. The motor mount, which is inside the body tube holds the rocket motor in place and prevents it from moving. The rocket motor itself is inside the motor mount. It is a safe but non-reusable item. It must be replaced for every single flight. It contains gunpowder which is all burnt out after one use. Finally, the fins keep the rocket moving straight. This keeps the rocket going the right way towards its destination or just keep going straight up.

// Ms. Mc: Excellent explanation of the function of each rocket part! 20/20 //

Rockets Experiment
**INTRODUCTION** The purpose of this experiment was to find out how the mass of a rocket affected the height of the apogee when the rocket was in flight. In this experiment, 6 rockets, all different masses were launched and the height of the apogee was found by using right triangle trigonometry. When the rocket is on the launch pad the force of gravity is acting on it, while the force of the launch pad is holding it up. During lift-off and powered flight thrust is pushing the rocket up. The force of the thrust is greater than the force of air resistance and gravity combined. During coasting there is no powered flight but the inertia of the rocket remains greater than the force of gravity and air resistance. When the rocket reaches its apogee there is a minute where the gravity and the inertia are the same. The rocket is overcome by the force of gravity and falls back to the ground. It was hypothesized that lighter the rocket the higher its apogee because it will take less time for the thrust to overcome the inertia of a lighter rocket rather than a heavier rocket. This results in a longer powered flight and higher apogee. **SUMMARY** The mass of the rockets varied little. The mass of the heaviest rocket was 44.5 grams while the mass of the lightest rockets was 42.2 grams. This yielded little difference between the masses of the rockets. However, the difference in the apogees was more prominent. The highest apogee was 81 feet while the lowest apogee was 53 feet. There was a direct relationship between the height of the apogee and the mass of the rocket. As seen in Graph 1, the heaviest rocket, at 44.5 grams had an apogee of 81 feet, the highest.Also seen in Graph 1, the lightest rocket, which had a mass of 42.2 grams, had the lowest apogee, at 53 feet. There was a direct relationship on this graph because for 6 of the 7 points, the higher mass was, the higher the apogee. The other point was the outlier. That rocket had a mass of the 44.4 grams, near the top but only had an apogee of 55 feet. The hypothesis was not confirmed because the heaviest rocket at 44.5 grams flew the highest at 81 feet and the lightest rocket, at 42.2 grams only had an apogee of 53 feet. As shown in a Graph 1, an obvious direct relationship was seen. This experiment had many possible errors. There were only 7 data points, which was not a big enough sample. Also, the people used to measure the apogees of the rockets were not always the same. The weather conditions varied over the few days that the rockets were launched.


 * Graph 1: Rocket mass and their Apogees**

__What is a quark? What types of quarks are there?__
A quark is matter that is inside protons and neutrons. It is considered the simplest matter there is next to the electron, which also can't be broken down. There are two kinds of quarks in protons and neutrons and 6 in all. The two types of quarks seen in protons and neutrons are up quarks and down quarks. An up quark is said to have a positive 2/3 charge and a down quark is said to have a negative 1/3 charge. As seen in Figure one a proton has two up quarks and one down quark, 2/3+2/3-1/3=1. This makes sense because a proton has a positive charge of one. A neutron has 2 down quarks and 1 up quark, 2/3-1/3-1/3=0. This also makes sense because a neutron has no charge. An electron cannot be broken down into quarks.


 * Figure 1: Quark diagram of protons and neutrons **


 * Question #2 **

__Which is older, the Universe or our solar system? Or are the same age? Explain__
The Universe is older because the Big Bang happened way before anything was created. Our solar system is pieces of matter held together by gravity and the sun at the center. When the big bang happened, it was so hot that it was impossible for even atoms to form, much less matter coming together, as seen in Figure 2. After the universe started cooling down to a low enough temperature then matter could start clumping together and gravity started happening more. The Universe is much holder because it took a long time for the temperature to cool down enough for large pieces of matter to start forming. In fact, now the temperature in space is only barely above absolute zero. (0 Kelvin)


 * Figure 2: Quarks and other particles after Big Bang**

Ms. Mc: Very good answers, figures, and captions. You didn't quite answer the questions though. What are the other 4 types of quarks? (-1/2). How old is the Universe (15 billion years) and our solar system (about 4.6 billion years)? (-1/2) 9/10

**Mindstorms Robotics Challenge and Programming**
Challenge #3 was the challenge where we had to program the robot to go to the edge of the table and then stop. The robot was supposed to stop right at the edge and say "watch out". The robot was supposed to start moving at the beginning after receiving a verbal command to start moving until it got to the edge of the table.


 * Figure 1: Robot Programming Code for Challenge #3**

Challenge #3 Programming

Block #1- A wait block that tells the robot to wait for a sound greater than 50 decibels with the sound sensor in port 2. The robot did not move until I emitted a sound greater than 50 decibels.

Block #2- A movement block that goes forward at 75% power for unlimited time. Servomotors B and C are activated. The robot moved forward and kept on going forward because it heard a sound greater than 50 decibels.

Block #3- A wait block that tells the robot to wait for a distance more than 30 centimeters with the ultrasonic sensor connected to port 4. The robot kept moving forward until the ultrasonic sensor encountered a distance greater than 30 centimeters.

Block #4- A movement block using servomotors B and C telling the robot to stop and brake. The robot stopped moving at the edge of the table because the distance from the table to the ground was more than 30 centimeters.

Block #5- A sound block that tells to robot to say "watch out" at 75% volume and letting it complete. The robot emitted a sound that said "watch out."