Reflection Blog

     On Monday during the "Blow up Kid" activity, we learned that the reason the bag inflates is because of air pressure. We also learned how to show this on particle diagram. Before that class period I didn't realize that air pressure played a role, and I would have assumed it was just the space the air took up when moved inside the bag.

     On Tuesday, we took a closer look into how a straw works. The straw works when you draw on it and remove the air, creating a vacuum and eliminated air pressure coming from the top of the juice in the straw. The air pressure remains pushing on the juice in the pouch, and therefore pushes it up the straw and into your mouth. Now, I understand how this works after all the particle diagrams and group discussions. 

     On Wednesday during the longest straw activity, we were testing how long of a straw is possible, and that scientist use similar ideas to measure air pressure, connecting to the manometer notes we took later on. From the straw activity, I took away that there is a limit on air pressure, and that a straw can't go on forever.

     We also took notes on the different measurement units of air pressure. We learned about millimeters of mercury (mmHg), kiloPascals (kPa), and Atmospheres (atm). They can be converted back and forth using proportions like we used earlier this year. I need to work on remembering the different equivalents of the units.

     When we were taking notes on Manometers on Wednesday, it tied all the ideas we learned so far together. Reading a manometer is different if it is closed or open. When it is closed, the gas pressure is just the difference in height of the two sides of the mercury. If it is open, you have to add or subtract the difference to the air pressure depending on if the air pressure or gas pressure is lower or higher. For me it is hard to remember to look if the manometer is open or closed before starting the problem or reading the measurement.