Printer Cartridge Colors

Wow, I really haven't posted in a while. Hopefully I'll have more time this week so I can catch up on my journal posts.

Anyway, just yesterday my printer ran out of color ink so I had to swap out the cartridge. When I got out the pack, I saw the box and laughed because the tricolor dots were yellow, magenta, and cyan. Until this past chapter on light and color, I never really thought about those colors except to know that it was a color cartridge with the correct number for my printer.

In that last chapter, we learned that light is made up of the primary colors: red, green, and blue. And that, in various combinations, these primary colors, make up the secondary colors: yellow, cyan, and magenta. However, this is not true for paints. Therefore, in order for our printers to print the colors in ink that appear in light on our screens, yellow, cyan, magenta, and black must be used. By using these colors, the printer is able to replicate all the shades of any color by varying the size of the dots printed in each color. Then, light will hit the dot combinations and the correct balance of colors will reflect back to our eyes allowing us to see the correct color/shade.

The Piano - Waves

Well, I was practicing piano today when I realized that I have yet to write a journal about the piano and all the good physics associated with it. Like the video in class mentioned, the piano is able to create such a wide range of volumes because of its impressive sounding board which can amplify the waves produced initially by the strings. On the other hand, the sound can also be dampened by holding down the damper pedal which shifts the hammers, causing them to only hit two of the three strings.

In addition, the strings are responsible for producing the different notes (higher or lower frequencies) corresponding to the different keys. The length, tension, and type of string/wire used help create the different notes/frequencies. Furthermore, another bit of information I recognized from class was the concept of octaves and accepted frequencies. In playing piano, if I had perfect pitch (which I don't) I would be able to recognize a note simply by hearing it. I would also be able to recognize that same note in a different octave. This is because similar notes in different octaves in fact have frequencies which are multiples of two of each other (for example, a note with a frequency of 100 Hz would be recognized as the same note but one octave lower than a note with a frequency of 200 Hz).

Overall, I thought it was pretty funny to realize that despite practicing piano every day for an hour or so, I've never connected it to physics until now. I got a good laugh out of my revelation and a fair amount of strange looks from my parents.

Stacking Boxes - Center of Mass

On Saturday, my parents and I went to help one of my mom's friends set up a bunch of new computers. There were about 16 Dell monitors and CPUs all boxed up. We decided to unpack them all first and stack the boxes on the side. Since we were busy setting up the computers, I guess no one was really keeping track of the boxes. Everyone would just put their box on the pile when we finished unpacking each component.

As a result, the boxes all fell over. The top three or four boxes were not pushed close enough to the wall and, therefore, the stack's center of mass extended past the support area and the tower collapsed.

Thankfully, all the important computer parts had been taken out so the only consequence was that we had to re-stack all the boxes.

Interestingly, we had the exact same problem later in the day when we were transporting a bunch of small boxes in handcarts. Because there was a hole in the back of the handcart, one of the small boxes fell through as we were moving them. As a result, the entire stack collapsed.

The box's center of mass extended past the small support area of the cart, causing it to fall through the gap. Then, because there was one less box supporting all the other boxes, they all fell off the cart.

Christmas Lights - Circuits

Since we've started learning about circuits, one of the first examples I thought of was with those old Christmas light strands. Although most of the newer ones are wired so that this doesn't happen, my family still uses one of the older kind to run up the middle of our tree. I always remember it as being a pain to set up because having just one of the bulbs broken causes the entire strand to not light up!

Of course, I am very familiar with this aggravating situation as I am always the one drafted to check the lights. I have to check each bulb to see if that is the one that needs to be replaced. Thankfully, we finally bought a newer strand this year. While before, the old strand wouldn't even light up if one bulb was broken this new strand still lights up and somehow bypasses the broken bulb. This makes it much easier to find and replace.

The reason the older strand was so difficult, was because it was wired like a simple circuit in which one broken filament breaks the entire circuit. As a result, the whole strand won't light up because the electrons won't flow through an incomplete circuit with the small voltage difference from the wall outlet.

Anyway, although this entry may be kind of out of season, I thought I'd write about our old Christmas lights since they were the first thing to pop into my head when I was thinking about current electricity.

Unfortunately, our Christmas lights and decorations are away in storage so I had to draw a strand of lights.

Uneventful Weekend - Centripetal Force

Well, I have had a fairly uneventful weekend (too much homework!) so when I remembered I had to do a Physics journal, I was quite at a loss for what to write about. Thankfully, I ran the wash yesterday so I'm going to write about the centripetal force in my washing machine. Unfortunately, I wasn't thinking about taking a picture of the wash so I only have pictures of the empty washing machine.

Anyway, the washing machine utilizes centripetal force during the spin cycle to remove excess water from your clothes so that they aren't dripping wet when you take them out. To do this, the little holes all along the sides of the washer are opened and as the washer continues to spin, centripetal force drives the water out. The water is small enough to fit through the holes and are therefore thrown out tangent to the circle by a lack of a normal force. As a result, all that is left in the washer are your slightly damp clothes which could not possibly escape through the holes.

So, that was my pretty lame journal for this weekend and now I have to go finish all the other homework that has caused my very uneventful weekend. Hopefully next time I will have a more recent physics concept to write about.

Physics in Magic - Static Electricity

Today my sister came home and told us all about this "really cool" demonstration their teacher did in science class. She said that their teacher seemed to "make the paper fly up and stick to the ruler like magic."

As she was describing this, I realized that it was most likely static electricity that caused the piece of paper to stick to the plastic ruler. So, I decided to try it myself. Using a plastic comb and a small piece of paper, I charged the comb by rubbing it vigorously against my shirt. As a result, when I brought it near the neutral piece of paper, it attracted the paper in an attempt to neutralize itself.

Specifically, the charged comb had either an excess or a deficiency of electrons. Since all objects want to be balanced/neutral, the comb was attempting to either gain or lose electrons in order to balance itself. To do this, it attracted the neutral piece of paper to attempt to lessen its charge.

I thought it was funny that I thought of static electricity when my sister described her teacher's "magic trick."