In Honor of Halloween...

...I'm doing a semi-Halloween-ish blog this week! Remember those toys called Crazy Bones? The plastic things that were in the shape of crazy things that you slid across the floor to hit the other persons'? Well, if you don't, they're pretty much like bowling, but both sides have pins and you use the pins to knock the other's stuff down...Okay, that was a terrible description. Haha. Anyway, I remembered these toys and decided to go find them. I found a vampire one and a Jack-O-Lantern one, so I used those. The vampire is (very badly) colored black, and the Jack-O-Lantern is (equally badly) colored orange.

I had my mom slide them on our wood floor and this is the result.Starting position.


And this is what happened. As we know, because of the law of conservation of momentum, (Mass of the Vampire)(Initial Velocity of the Vampire)+(Mass of the Jack-O-Lantern)(Initial Velocity of the Jack-O-Lantern)=(Mass of the Vampire)(Velocity of the Vampire after impact)+(Mass of the Jack-O-Lantern)(Velocity of Jack-O-Lantern after impact). The vampire toy stopped in the exact same place where the Jack-O-Lantern started, so we know that the initial velocity of the Jack-O-Lantern is zero and the final velocity of the vampire is zero.

Therefore, (Mass of the Vampire)(Initial Velocity of the Vampire)=(Mass of the Jack-O-Lantern)(Velocity of Jack-O-Lantern after impact)

I don't really know, masses or the velocity, so this is as far as I can take this. Happy homecoming week, everyone, and Happy Halloween! Think about my vampire and Jack-O-Lantern crazy bones while you're trick-or-treating next Saturday! By the way, Jack-O-Lantern is a huge pain in the butt to type repeatedly...Just fyi. :D

What I did this weekend...>_O

Yeah...As you can probably tell by this picture, this weekend wasn't a very good one for me. I was driving and this hideous mess happened...JUST KIDDING! Haha. I'd get murdered if this happened while I was behind the wheel. This is actually my mom's friend's car. He got into a little fender-bender with a couple other cars. Someone rear-ended him and pushed his car into the car in front while sitting in traffic. Fortunately, he was unscathed, and he still ended up going to work (talk about dedication!).

The front of this car demonstrates a concept straight out of the textbook. We learned that the fronts of cars are designed to crunch like that, in order to prolong the time of impact, even though this is just a tiny crunch, it still has the same concept. Momentum is mass times velocity. Net force equals change in momentum over change in time. If the time is increased, but the change in momentum stays the same, the net force decreases, thus lessening the force of impact when the driver feels it, which is kind of the point of the crunch-able front of cars.

Imagine what could have happened if cars didn't crunch like that! :O

Tension Between Siblings

For the past couple days, I've been freaking out about what to do for my blog entry this week. Nothing struck me until just about an hour ago at dinner.


As you can see, my headphone cords are uneven. They are purposely like this so that you can put in one side, and pull the other side around the back of your head to keep the cords out of the way more. (If you don't get what I'm saying, track me down at school one day and ask. Haha.) Anyway, in the picture, the side I have in my ear is the shorter side. However, this style of headphones is unfortunately harder to share.

At dinner, my sister and I were eating and listening to music. I found that the earphone in my ear fell out much more often than my sister's. It occurred to me that it was because I had the shorter end.

I then proceeded to imagine the problem from our text book with the monkey holding onto a piece of string, but the lengths on either side of the monkey's hand were uneven. Our job was to find out which string had the higher tension, and it ended up that the shorter side had more tension because the angle the string made with the horizontal was greater.

Now I can explain why my headphone fell out more than the one I gave my sister. Unfortunately, only my classmates would understand. My family just gave me blank stares and absent-mindedly nodded their heads while I babbled. :]

Volleyball Physics

Last weekend, I went to one of my sister's volleyball games. (She's the one standing closest to the net by the way.) Anyway, while I was in the bleachers, I was intensely thinking about a topic to make my blog on. It wasn't until halfway through the game that I realize there was physics happening right in front of me.

Everytime the ball was bumped into the air, it made a perfect parabola with its path. It stopped moving when it hit a certain point and came back down to another player's arms...or the floor. I knew that was because of gravity acting upon the ball. I got so excited that I started babbling about physics to my mom and dad who were trying to watch the game. When they told me to stop talking, I whipped out my camera and started taking pictures.

In the pictures above, I colored over the ball in bright green to make it more noticeable. If you look from left to right in the rows, you can see the ball's arc and its highest point, which happens in around the second picture. After that picture, the ball begins to come down.

My sister, who is at the net, sees that the ball is not going to make it over, judging by its arc, and jumps to tip it over in the last photo. Little did she know, she used physics in her volleyball game!




This is totally unrelated to volleyball, but I found it interesting. Lately, I've been seeing physics everywhere...Even while I'm driving. No, not in acceleration or anything, I see it is street signs as well...
The first thing I thought of when I saw this sign was...FREE BODY DIAGRAM. If you rotate it a little, it could totally pass for one, am I right? I freaked out when I saw it, and immediately told my mom to take a picture. Okay, it's a little bit of a stretch, but trust me, from now on, when you see one of these yellow street signs, you're going to see a free body diagram. Haha.