I have been wanting to make an x-ray machine for quite a while, but only recently found a tube and power supply that were not too expensive. An x-ray tube works by shooting a beam of electrons from an aluminum cathode (C) which strike a platinum anode creating x-rays. The anode (A) is angled so that the x-rays are directed out the tube.

X-ray tubes require a very high voltage in order to operate so I also got a 25Kv (25,000 volt) power supply which I will use to run my tube.

X-rays are much smaller than light waves which means they cannot be seen with the naked eye. In order to see the x-rays I will use an x-ray intensifying screen which will produce photons when struck be x-rays. Because x-rays are a form of radiation I will use a camera to look at the intensifying screen so that I don’t have to be in the room while the tube is powered on. I will also make a switch that can be triggered from outside the room.

 

The Fold by Peter Clines is a book about a guy named Mike Erikson who is a school teacher with a photographic memory. One day his friend offers him a job to go out into to desert and investigate a team of DARPA scientists who have invented a doorway that folds dimensions and shrinks distance-so that a one step through the door can carry you hundreds of feet. The scientists claim that the doorway is completely safe but there is evidence that the door might not be what it seems. As Mike continues to investigate he begins to discover what might actually be happening, and if he’s right the project could destroys everything.

I like the style of writing in this book, it reminds me of another author Michael Crichton who’s books  I also like. I also enjoy how some of the scientific concepts are based off of real ones, and how well he explains them.

This week we attempted the first launch of the sugar rocket. We packed one of the rockets and added a stick for stability, then we brought it outside for the launch. We used a peace of PVC pipe clamped in a vice as a launch pad, we stuck the stick in the PVC so that it was sticking straight up. When we tried to launch the rocket the engine burned but the rocket was not able to lift off. The second launch we tried making a smaller hole in the engine and that seemed to help a bit, the rocket made it off the launch pad this time but it only flew a couple of feet. Next we tried mixing different fuel with more potassium nitrate in it, I was hoping that this would make the fuel burn faster because the potassium nitrate makes oxygen when it burns. Unfortunately the next launch with the new fuel failed too, the fuel actually burned slower with the extra potassium nitrate. I’m going to trie to research how to make the fuel burn faster so that next week we can try again. We also might try making lighter rockets that need less thrust in order to fly.

This week we made two test rocket engines. We started by putting some clay kitty litter in a coffee grinder and grinding it into a fine powder. Next we made a stick that we used for measuring and packing the powders in the engine. Then we filled one of the rocket engines with clay powder and pounded it down with the stick. Next we ground up the potassium nitrate and mixed it with the powdered sugar. We poured the potassium nitrate and sugar mixture into the engine and packed it down with the stick, then added one last layer of clay as a cap. The last step was to drill a hole through the middle. The hole would act as a nozzle and it would make it so that we could light the engine from the back and have it burn down the core. The rocket engine was now ready to fire, so we clamped it in the vice and used a remote ignition system to fire it. The engine ran perfectly and we did one more test with the same results. Next week we will fly the engine for the first time.

How Newton’s Laws of Motion Apply to Rockets.

Newtons first law states that a object in motion will remain in motion and a object at rest will remain at rest unless acted upon by an outside force. This is easier to observe in objects with a large mass like a train for example. A train has a lot of inertia so when it is moving it would like to remain moving and it takes a great effort to stop it. The word inertia comes from Latin and literately means laziness. Things than have inertia are lazy. Lazy things like to keep doing what there doing.

Whether or not a rocket should have inertia depends on what you are trying to do. If the rocket has been launched then inertia is good because the rocket needs to overcome drag from the air. But before you launch inertia is bad because a force (thrust) must be applied to overcome the inertia and the more you have the greater the force required to overcome it. The best rockets have a small mass and are aerodynamic, this gives them a high thrust to mass ratio. Once the rocket is moving the drag should be minimized by the shape of the leading edge of the rocket, reducing the rate at which the rocket is slowed by the air.

Newtons Second Law.

There are many forces that act upon a rocket. A propulsive force is required to move the rockets while it is siting on the launch pad. The rocket can be made to move faster by either increasing the force and/or decreasing the mass. How quickly a rocket increases speed off the launch pad is called acceleration. A rocket’s acceleration is equal to the force applied divided by the mass (a=f/m). As force increases acceleration increases, as mass increases acceleration decreases. Re-arranging the formula gives you the classic way of describing Newton’s second law, force equals mass times acceleration (f=ma).

Newtons Third Law.
For every action there is an equal and opposite reaction. For example, if you hit the table with your hand the table hits back with an equal and opposite force. A rocket is able to lift off the launch pad because the acceleration caused by the expanding exhaust gas is able to overcome the rockets inertia. The same principle applies to airplanes, the only difference is that rockets are continuously accelerating as they burn fuel and their mass decreases.

 Today we experimented with potassium nitrate and sugar reactions. So far we have only tried a 1:1 ratio of sugar to potassium nitrate but next week we will start to test deferent ratios. We tested the fuel in a cup just so we could see the reaction better but next week we will start construction of the engine. My idea for the engine is to fill a PVC or copper pipe with the fuel and put a hole through the middle to act as a nozzle. I will light the engine from the top so that it burns from the top down and hopefully keeps the nozzle intact for as long as possible. If that doesn’t work I’ll have to make a nozzle out of something else like clay maybe. We also made the rocket bodies today which we made from PVC pipe with cardboard nosecone and fins. They don’t have parachutes currently, but that might be something that we are going to look at it the future.

A sugar rocket is a rocket with a sugar based fuel. The fuel has two main parts the fuel and the oxidizer. In a sugar rocket the fuel is sugar and the oxidizer is usually potassium nitrate, other things can be added to the fuel to effect how it looks when it burns but I’m not going to be adding anything to mine. For the fuselage of the rocket I’m going to use PVC pipe and I’ll use cardboard for the fins and nose cone. I also got a manuel altitude finder so that I can see how high my rocket goes. After I perfect the fuel mixture and rocket design I might try to add a parachute that deploys when the engine burns out. My idea for the parachute deployment is to make a small rocket engine on top of the main one facing back at the parachute so that once the main engine burns out it will ignite the small engine blowing the parachute out.

I’ll write a second part with pictures when I have finished building the rocket.

Harry Eng was the first to popularize impossible bottles. He was a magician, inventor, and school teacher who loved to make people think. Harry put all kinds of things in his bottles, most of them bigger then the neck of the bottle. The bottles where always undamaged and the objects always went in through the neck of the bottle. Some of the things he was known for putting in his bottles were coins, decks of cards, padlocks, books, shoes, and scissors. His trade mark was a knot usually bigger then the neck of the bottle and sometimes so big that it touched the sides. When Harry died he took many of his secrets with him, however there is now a small group of people world wide that have discovered some of the secrets. I recently figured out a couple of them including scissors, a padlock, and a small motor. I have also put a match box and a servo motor in a bottle. The process is difficult and frustrating but the result is vary satisfying.

I discovered the impossible bottle about two years ago, and started thinking about how it was done.  After two years of having it in the back of my mind, the solution came to me. I think it’s interesting that you can’t find the solution on-line, some forums give small hints but the solution is never revealed.  After putting something in and knowing it worked, was very exciting.

This is a picture of my hand held Tesla coil that we were experimenting with today. The arc between the tip and the pear is emitting light because electrons that have been shot off the tip collide with an electrons orbiting atoms. When they collide the orbiting electrons jump up to a high energy state and absorb an electron, then they fall back down emitting a photon. That is why you can see the arc. The arc is also made up of plasma, which is a cloud of free floating electrons that whiz around. Sometimes the flying electrons smash into an oxygen molecule and split it apart into two oxygen atoms. If an oxygen atom runs into an oxygen molecule they combine to form an ozone molecule O₃ which is three oxygen atoms bonded together.

I had fun experimenting with the Tesla coil with my classmates.

This Wednesday I did a flight in N2723L a 1967 Cessna 172H. I did the flight in two parts, part one consisted of preflight, fueling, and photoshoot. The preflight is the inspection that pilots do before every flight. Some of the things that are checked during the preflight are tires, breaks, wing strut, leading edge of the wing, pitot tube, fuel vent, wing tip, ailerons, flaps, fuselage, antennas, elevator, rudder, oil, etc. Next we refueled. When calculating how much fuel we need for a flight we use a fuel burn on ten gallons per hour for this plane. I wanted to fly for about two hours so I new I needed 20 gallons of fuel plus 30 minutes ( 5 gallons ). You have to bring at least 30 minutes of extra fuel for each flight. Now it was time to go flying! After takeoff we made a right turnout towards the river. We wanted to fly over the upwind side of the hills so that when the wind blows it will be deflected up the hill and help us climb. Our goal was to climb above the clouds so that we could take some pictures. After flying around above the clouds for a while we found a hole in them and started to descend. We entered the traffic pattern for runway 25. After landing we taxied back to the FBO (fixed base operator) so we could pick up my parents. We took off again and used the same strategy as before to climb. We started to fly towards Mt. Adams but my mom got sick so we turned around before we got there. We made the same traffic pattern as before and I made a nice approach and a very nice landing. I like flying because you get to cheat….. gravity, death, and common sense.