Jaren

__ Entry 1 __ 3/24/2011

**Electronic Devices**

Analog signals are different from digital signals because digital signals jump from one piece of information to the next and analog uses waves. Analog waves work smoothly in time, so the waves are smooth curves. Digital signals are transmitted in sections. When each little chunk is put together, it created what we see and hear. Semiconductors are useful in electronic devices because they do not conduct electricity as well as conductors but they can be added to and made more or less conductive. Diodes make a one way path and are used to convert an alternating current to a direct current. Transistors are used as switches to block electricity or let electricity pass through. Integrated circuits are small pieces that have many diodes and transistors inside of them.

Electronic devices are important to our mission in Mars for many reasons. We will need to create a spaceship that will use computers to control it. For those computers we will need electronic devices. We will also need some sort of camera to take pictures, and a computer to examine the pictures for life. That is how we will need electronic devices for our mission to Mars.

Great job! Nice and straight to the point. Maybe a little too short, but I think it covers everything it really need to. Great job!

Arash

Ms. Mc - Good general overview of electronics and how we might use them on a mission to search for life on Mars. The second paragraph needed a little more detail, however. 9/10

__Entry 2__ 4/4/2011

** The History of Rockets **

Around 100 BCE, a Greek inventor used water vapor to turn a ball. This was the first time steam had ever been used to propel anything. It used Newton's third law, for every action there is an equal and opposite reaction, to make the ball spin the opposite way that the steam was coming out. The idea of using steam and Newton's third law to move an object has led to some inventions that have changed the world, including the rocket.

One of the inventions made from that idea was the rocket. Originally rockets were made with gunpowder. The Chinese put gunpowder-filled tubes on arrows to that the arrow would blow up when it hit something. Later they realized that the tubes could launch themselves. The Chinese used the first rockets, which they called arrows of flying fire, against the Mongols during their war. After the war was over, the Mongols produced their own rockets, which might have been how rockets ended up in Europe. In Europe, many experiments were done to find the best rocket. Robert H. Goddard was the first to use liquid as a propellant for rockets. He was determined, and after many attempts, he finally made a rocket, propelled by liquid oxygen and gasoline, that flew. Right before World War II ended, Germany unveiled their V-2 rocket that could cross the Atlantic Ocean. That began the idea that rockets really could be used for fighting. The USSR and the US began a fight for the best weapons, known as the arms race. People realized that the rocket had the potential to go into space! The Soviet Union released their first satellite, Sputnik I. This pushed the US to fight back. The United States formed an organization that would be in charge of the space venture. They named it the National Aeronautics and Space Administration.

Since then, many rockets have traveled into space. Along with other modern technology, rockets have led us to a much better understanding of the universe.

Ms. Mc - Great summary of the history of rocketry. Good job with your drawings too! Please be sure to label your photos/drawings with a figure # and title. 14/15

__ Entry 3 __ __Rocket Simulation__ 4/3/2011 Make sure your sound is turned on. The video should run automatically. To stop it press the red circle on the top right corner. To restart or play it, press the green flag on the top right corner. media type="custom" key="8945612"

__Entry 4__ The nose cone directs the air around the rocket so the rocket is more aerodynamic. The body tube is the main structural part of the rocket that holds the motor, recovery wadding, and the recovery system. The recovery system slows the rocket's falling speed so the rocket is not damaged and can be used again. The launch lug keeps the rocket straight as it launches off the launch pad. The recovery wadding protects the recovery system from the heat of the motor. The motor mount holds the rocket motor in place. The fins keep the rocket from traveling in different directions. The rocket motor propels the rocket and makes it move.

//Ms. Mc: Good definitions. The motor mount also is inside the rocket (-1/2). Please include the date and a title for your entry as well (-1/2). 19/20.//

__Entry 5__ 4/20/2011

The purpose of the experiment was to determine if the mass of the model rocket affects the rocket’s apogee. When the rocket was on the ground, the force of gravity pulled it toward the center of the earth, but the ground has an equal force which pushed the rocket up. When the rocket was launched, the force of thrust from the engine was greater than the force of gravity making the rocket fly up. While the rocket is flying, air resistance was acting against it, helping gravity to slow the rocket down. At apogee, the rocket lost its inertia from the thrust and gravity began to pull it back to earth. It was hypothesized that the rockets with more mass would have a lower apogee, and the rockets with higher mass will have a higher apogee, because the engine would have an easier time lifting a light rocket than a heavy rocket.

The hypothesis was mostly confirmed. The less massive rockets flew higher than the more massive rockets, as shown in Graph 1.

The masses were 41.5, 44.2, 44.4, 45.2, 45.4, 45.5, and 46.9 grams. The apogees were 62, 69, 82, 85, 90, 93, and 119 meters. The only problem was that one rocket weighed 41.5 grams, much less than the others, and flew only 69 meters high, the second lowest apogee. It probably weighed less because it did not have very much paint on it. The reason that it didn’t fly very high is that there could have been a gust of wind, bad fin placement, or bad measurement. It also could have been missing a piece that would’ve helped it fly better which could explain both the mass and apogee. The data had an inverse relationship which makes sense because according to the hypothesis, the lower the mass, the higher the rocket would fly, and the higher the mass, the lower the rocket would fly. The test might have had some error. Each rocket was only tested once, so the measurements may not have been perfect. That could affect the results because the data could be incorrect. Also, the rockets were made by hand, so there could have been measurement errors which would lead to rockets not working right.

__Entry 6__ 4/21/2011

Quarks are what make up protons and neutrons. There are ups and downs. The ups are worth 2/3 of a charge and the downs are worth -1/3 of a charge. (Figure 5) Our moon came to revolve around Earth when a planet about the size of Mars collided with the Earth. Most of the mass added to the earth, but some dust and dirt flew up into the air and formed the moon. (Figure 6)

// Ms. Mc: Good but could use a few more details to completely answer the questions. There actually are 6 types of quarks (-1/2). 9.5/10 //

__Entry 8__ 5/5/2011

For this challenge, the robot had to follow the blue tape straight, then turn right on the tape, then straight, point turn left, and then backwards to the star. At the star, the robot had to make a 720 degree turn. Finally the robot mde a clapping sound and displayed a smiley face. Video 1 shows the robot completing the couse. media type="file" key="JpH_challenge1.mp4" width="300" height="300" Video 1: The Robot Completing Challenge 1. **Block 1:** A movement block telling the robot to use servomotors C and B to go forwards at 50% power for 3.75 rotations. **Block 2:** A movement block telling the robot to use servomotors C and B to make a point turn to the right at 50% power for 170 degrees.
 * Block 3:** A movement block telling the robot to use servomotors C and B to go forwards at 50% power for 1.75 rotations.
 * Block 4:** A movement block telling the robot to use servomotors C and B to make a point turn to the left at 50% power for 170 degrees.
 * Block 5:** A movement block telling the robot to use servomotors C and B to go backwards at about 50% power for 1.25 rotations.
 * Block 6:** A movement block telling the robot to use servomotors C and B to make a point turn to the left at 50% power for 1390 degrees.
 * Block 7:** A sound block telling the robot to play the sound “!Applause” at 75% volume.
 * Block 8:** A display block telling the robot to display a the image “Smile 01.”
 * Block 9:** A wait block telling the robot to wait 3 seconds before doing the next action.
 * Block 10:** A display block telling the robot to clear the display.