Particle Motion

For simplicity's sake, we played with simulations on Thursday, I think. We had done quite a few of the simulations, so I'll do a brief summary on each one and basically what I learned from the experience. The first was predicting where the red particle will go among a group of blue particles and I made the reasonable guess that it would flow with the other particles, but it was far too unpredictable. Then we were told to think back to the Febreze experiment we did in class. What did the blue particles represent and what did the red one represent? Well obviously the blue was the air, because there was an abundance of them in the beginning and the red the Febreze as it flowed through the room. The next one was asking for the behaviors of molecules in a gas. Well, to put it simply, they were completely random. Their speed varied between the particles, they moved everywhere with no specific direction, and how when they collided with each other or the wall, they transferred energy, which gave them a boost of speed. However, no energy was gained during the process. Then, we were asked how temperature affects the speed of particles, which was simple enough. The hotter the temperature was the faster the particles moved, because the heat actually transferred its energy to the particles. The last experiment we were asked to complete was the difference between Helium and Krypton gas molecules. Well, watching the simulation, it was easy to see that the red particles or Helium was definitely faster than the Krypton, but if you increase the temperature for only Krypton then they would be moving at the same speed. I learned a lot through the simulations about molecules, energy transfers, temperature, etc. to say the least.

Temperature

Last week, we had done an experiment with temperature using water and alcohol. Two tubes, one of water, the other of alcohol, were placed in one of the beakers on top of some kind of heater. We were to mark the tubes of wherever the liquid reached after the thermometer increased by 10 degrees Fahrenheit each time. Immediately, we noticed that the alcohol rose faster than the water, even though they were at the same exact temperature. Later, we figured out that was because that were both composed of different substances, which increased and decreased at different speeds. That wasn't the only experiment we attempted that day. We had two beakers, one filled with cold water and the other with hot, and placed a few drops of dye in each one. The hot beaker had red food coloring and when the food coloring entered the water, everyone could see how fast the red expanded through the water and finally blended within a few minutes. That's, because the particles were moving faster and when they move faster they are able to expand at a high rate. When we placed the blue food coloring in the cold water that was refrigerated the night before, however, it slowly spread out through the water. After five minutes, it still barely even expanded unlike the red food coloring that was already fully blended. We figured this was because the cold particles moved slower. The slow the particles moved/collided, the slower it would take for a substance to combine with another. We, also, learned about the different types of thermometers, how they worked, who invented them, and if they were still used today. We learned a lot that day, though it was centered all around temperature, like how substances rise and fall at different rates, how food coloring in hot water expands faster than if it was in cold, and all about thermometers and how they're important to us.

How a Straw Works

We started with a video about two guys in Britain who decided enough was enough. No more having to walk like 6 meters to get a coke from the fridge. They were going to use a giant straw to do so which though at first didn't seem educational, ended up explaining how a straw works. Before we actually learned much about it, though we had to test this out ourselves, we were given Capri suns and told to suck it. We learned that the reason why we could suck it up was because of a vacuum like effect. When we sucked in the juice, the air inside the straw was pushing the liquid down, but when we eliminated the air, the juice could be sucked up, but there was another factor as well. The air on the outside. It pushed on the juice as well, allowing it be sucked upward when there was little air on the inside, because it was stronger. We also learned when we tried this with a giant 10 meter straw that the narrower the straw was the easier it was to suck up the liquid. We, also, learned that even if there were such thing as a perfect vacuum, the water would only reach 10.3 or somewhere around there meters before it couldn't go up any higher, because the air pressure that supported it was too weak, well not as strong as the pressure on the outside. We learned that sucking up liquid using a straw was far more complicated than we imagined.

Garbage Bag Experiment

When we first started this project, it was in the beginning of the week and we were just learning about air pressure. Our main objective was to blow up a garbage bag using straws with someone actually sitting on top then we were supposed to explain how the bag expanded. We concluded that it was because of air pressure. We learned that even though there was little air in the garbage bag to begin with, there was still pressure that forced the bag up in certain places and down in others when the air pressure outside the bag was stronger. It took a bit to fill the garbage bag with air and raise Reilly, I think that was his name, off the floor. We added more air particles into the bag and since they were warmer, they collided with each other more often, creating a greater air pressure. I guess this explains why Reilly felt the garbage bag, well the air pressure inside it, pushing him up off the ground and why the bag was able to expand. I've known that if blow air into something, in most cases balloons, then it will expand, but I guess I learned that there is air pressure that is a key factor, on the outside it presses in and on the inside it presses out, that if the pressure outside is greater it contracts, but if the pressure inside is greater it expands.