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That was some tsunami...all of like 1 or 2 feet of it...but at least no one got hurt and Kiss Me, Kate still went on! The tsunami warnings were triggered because the 8.8 magnitude earthquake in Chile triggered some unusual patterns in the ocean. The reason why an earthquake thousands of miles away can affect us here in Hawaii is conservation of energy! The earthquake created a lot of kinetic energy which needs to be absorbed by something else when the earthquake stops because energy cannot be created or destroyed. The earthquake was the initial force that created the unusual waves and the tsunami scare on Saturday. The earthquake and the waves were examples of oscillations. There were both transverse and longitudinal waves involved because the particles moved both parallel and perpendicular to the direction of the waves. However, the particles do have net motion because an earthquake or tsunami would not create any damage if everything returned to its original spot. An estimated time of the tsunami arrival in Hawaii could have been predicted by using the equation for the speed of a wave: v=wavelength/ time, if the speed of the waves produced by the earthquake in Chile were known.
Because we recently studied circuits, I thought about the time when all the electricity in the living room went off while my dad and my brother were playing video games on the Xbox 360. My dad turned off the fan in the living room and then went in the garage to on some kind of switch. At the time, I didn't really understand what happened, but thanks to physics I do now. There were too many appliances running in the living room, so the current in the circuit was too high. The circuit breaker was tripped in order to prevent overheating or an electrical fire. My dad had to turn off an appliance in order to reduce the current and reset the circuit breaker in order for electricity to run in the living room again. The different switches in the box correlate with the different circuits running in each room of the house. The whole house must not be connected in series, otherwise electricity would only run if every outlet had a running appliance. However, the circuit breaker for a room must be connected in series with the outlets in the room in order for the tripped circuit breaker to shut off all the electricity in the room. Circuit breakers are good alternatives to fuses because fuses need to be replaced every time they are blown (as we discovered in the lab when we connected them in parallel...), but with circuit breakers, you can just turn the switch to restore the flow of electricity.
I was thinking about what to write about for my next blog topic when I saw this little porcupine thing on my desk. It's pretty cute and I'm not quite sure whether it's meant to be a magnet, a paper clip holder, a paper weight, or all of the above, but it definitely involves physics! I started playing around with the paper clips and the magnetic porcupine and this resulted in the structure in the picture. I realized that it relates to the last chapter about electromagnetism. The paper clips gain a charge when in contact with the magnetic porcupine because the opposite charges attract. The charge is transferred to other adjacent paper clips, creating the structure above (which took a lot of patience...). The forces in this structure had to stay in equilibrium so that I could take the picture. The downward force of weight on the hanging paper clip must be equal to the magnetic force holding it up. Also, there are torque forces (rFsintheta) acting on part of the structure (where the paper clips are halfway overlapped). The torque forces in both directions must be equal for the system to maintain equilibrium.
