Pippin's Question Box

Why is the fireplace more effective at heating your house than leaving your oven open?
Explain: heat transfer, free convection vs. forced convection, surface area Best

Got Science?

Got science, anyone? Sorry, I couldn't resist. Hope everyone is enjoying their spring break despite the rain!

So, to the question box. My source for this is not a link, a book, but an engineer!! So, I have no link for you. The question was: How does jello solidify? The answer lies in the concepts behind heat transfer.

We all agree that jello needs to be cooled down in order to solidify, correct? So, really, jello solidifies according to how heat is lost- where the jello loses heat, it solidifies. However, the heat needs to be transferred to something else in order to "lose" heat- by conservation of energy, as we learned in class. Thus comes in handy dandy convection. Convection is heat transfer using a fluid- i.e., a liquid or gas. The fluid that is doing all the transferring in the jello scenario is not the jello itself, but the air around the jello. If we put jello in a pan, it has contact with the air. As the heat from the jello warms up the air around it, the air rises and starts moving, allowing cooler air to take its place. This type of convection, caused solely by the differences in temperature, is called free convection. But let's say I wanted to serve the jello, or in my case, the almond jelly/tofu-ish thingamajig for desert, and it was already five o'clock. Oh no! How would I speed up this process? Well, it might not be good enough to get it ready in time for desert, but it would speed up the time it took if I placed a fan that blew cold air next to the jello- forcing the air to move faster, taking more heat with it. This is called- you guess it, forced convection. So, the answer to the question? The jello solidifies all around. Wherever the jello (or it's pan) has contact to the air, it will solidify there first, so the last to solidify would be the middle. Now, here's a challenge: apply these concepts to the next question box, coming up soon.

By the way, Bubbly happens to have some good links if you really want them!

Pippin's Question Box

How does jello solidify? (from the top down, sides in, bottom up, etc.)
Explain these concepts: Heat Transfer, Free Convection vs. Forced Convection Best

Got Science?

What causes nausea? The answer: other stuff.

There are a lot of things that can cause nausea. Nausea itself, though, is not a disease. Let me repeat this: (in general), feeling as though you're going to hurl is not a disease. It's a symptom, an indicator of something wrong, a sign from your body, but it's not alone (in other words, it's a hint for your doctor to figure out what's wrong with you.) Of course, it's not necessarily something really wrong with you, it could just be motion-sickness, but your body doesn't decide to throw up for no reason.

That leads me to the real point of the question: what causes nausea that is associated with motion-sickness? In other words, what causes motion sickness? Motion sickness is caused when the various places that collect information about your movement, position, etc. conflict with each other- primarily being, in order, your inner ear, visual input, and nerves around your body and in your muscles. When all these places send signals to your brain, your brain makes sense of it all to create a general idea of your movement. For instance, right now my brain can make sense of the fact that I'm sitting still, but my fingers are moving to type up this post. Therefore, my brain isn't confused and I don't feel sick. However, if for some reason my house suddenly got up and started walking, my eyes don't see that I'm moving because all I see is my house (frame of reference, anyone?). My inner ear, on the other hand, can feel that I'm moving as the house is, er, walking. They conflict when they get to the brain, my brain is confused, and presto! Motion sickness on the menu! I don't really know what happens in between the brain getting confused and nausea, but I'd guess that the reason why our brain signals our stomach to reject its contents is that it's so busy trying to figure out whether or not it's moving that it neglected the stomach. Just a guess...

Here are my links:
http://www.medicinenet.com/motion_sickness/article.htm
http://www.medicinenet.com/nausea_and_vomiting/article.htm

Pippin's Question Box

In honor of Brain Awareness Week, we're taking a break from physics:

Choose an article from Neuroscience for Kids and summarize what you learned. If you don't know what to choose and want to do ol' Pippin a favor, explain action potential. I don't quite get it!

Got Science?

So what is a gravity wave???

Now, I'm no physicist, but I do know how to do a bit of research- or rather, simply use the NASA link on my page and search the archives. Anyway, seeing as this is a weird question that has a cool answer, I'll discuss it.

Light comes in waves. Water comes in waves. Homework comes in waves! So why not gravity? Gravity waves are hypothetical waves that are kind of like "ripples" in space time. Think of it this way: space-time (that stuff we're sitting in) is a huge sheet. Whenever I put an object on it, like Sunnyd's yellow bouncy ball (the sun!), it causes a little dent in the sheet (that is, if the ball doesn't bounce off...).

From: Gravitational Waves

That little dent, in this instance, is gravity. Now, say Sunnyd got ahold of a bowling ball and put it on the sheet. Providing that you can still hold it, that sheet will be jiggling a little at first, right? Think of that bowling ball as some supermassive object, like... a huge star, and those vibrations are gravity waves- like ripples in a pond. As I get a little mischievious and start shifting that bowling ball around, even more "ripples" are made- thus, more gravity waves. Of course, that's an oversimplified explantion, so if you can rectify this, feel free. These are extremely hard to detect as they get to us, though, because all those gravity waves from the black holes nearby (not that near! No need to panic) get fainter and fainter as they move away from the source. A new satellite, LISA, is expected to launch in 2011 to detect these gravity waves. My source is: http://imagine.gsfc.nasa.gov/docs/features/topics/gwaves/gwaves.html.

I'd like to commend everyone who has answered this first physics question box, but some things to note for next time:

Make sure to paraphrase your answers ( I blame myself for this, so it isn't your fault)

Make sure it sounds vaguely scientific- but if Sunnyd or I can't decipher it, you've gone overboard!

Good work everybody!

The Brain, Part Two

Happy Brain Awareness Week, everyone! No joke, March 15th- 21th is really, truly brain awareness week- and I didn't make this up.

I have just discovered that there is a book from the Society for Neuroscience that you can read online! It is called Brain Facts and is supposed to be a (74 page long) introduction to neuroscience. Pretty amazing, isn't it?

Oh, my brain hurts- figuratively. The lesson for part two shall be neurons. Neurons are the cells that make up your brain- cells, if you recall, are not just stuff, but the basic units of life. Before you jump on me with a dozen "neurons aren't the only stuff in your brain," though, note that, yes, neurons aren't the only stuff in your brain. However, they are the most well known and are the basic working cell in your brain. There are three main parts: the cell body, or soma, the axon, and dendrite. The cell body is something we should be familiar with, since we covered cells in genetics: it contains the nucleus and the organelles. Dendrites and axons are specialized extensions (like an arm and a leg, but neurons don't walk) of the neuron. Wait, a picture would help, wouldn't it? Here we go:

Dendrites, those little things that branch out from the cell body, receive signals from other cells. The axon sends signals out. Think of it this way: dendrites in, axons out. Simple enough, right? Take a breather to put that in your head. Ready? The points at which two cells contact each other is called a synapse. I say contact because they don't actually touch. Now, this vocabulary is nice and all, but how do the cells work, you ask? Good question- I don't really know. The gist of what I do know, however, is that the nerve cell, when at rest, has a natural (I believe negative, though I'm not so sure) charge. However, when a cell sends a signal to the neuron, it generates an electric charge that goes to end of the axon, what the diagram depicts as the presynaptic terminal, which then releases neurotransmitters (chemicals) to the next neuron, which generates an electric charge, etc. If you want something more detailed, check out this website about the action potential, which explains how electrical pulses move along a neuron. In fact, if someone can explain how action potential works to me, I'd be delighted! In order to help the electric charge move along, the axon is covered in a sheath of mylelin. As the neurotransmitters (remember, chemicals) are released at the presynaptic terminal in little packets called quanta, it travels across a little gap called the synaptic cleft and binds to receptors on the next cell, which may cause that cell to fire an electric charge as well. Now, I don't know about you, but it's going to take a little while for that to soak in my brain. Look for more information in Part Three of The Brain!

Disclaimer: Seeing as I'm a student, this information may be invalid or not quite true- I'm still trying to figure it out and organize my thoughts in these posts!
Sources: http://www.sfn.org/skins/main/pdf/brainfacts/2008/brain_facts.pdf

http://nobelprize.org/educational_games/medicine/nerve_signaling/

http://faculty.washington.edu/chudler/cells.html

Pippin's Question Box

New theme: (drumroll!) Physics!!

What is a gravity wave? Best

Science Buzz: The Brain, Part One

I've been checking out a website from a club about the brain and discovered that it was The website for neurology- a treasure trove of information! So I've decided to start to post things that I learn in hopes that I'll remember it past today. (Look at Neuroscience for Kids on my Cool Links! gadget)

What is the most important three pounds of stuff in your life? If you said your laptop, your cell phone, and your ipod, you're wrong (or at least, you should be). It's your BRAIN! Yes, this mass of tissue and neurons and chemicals and electrical energy dominates everything about you. Without it, you'd be food for the buzzards. And so, let us begin the journey into the most important thing in our life: our brain.

To start off, let's look at a picture of a brain (from the website):

Obviously, your brain isn't this colorful normally. But since we're going to dicuss the lobes of the brain, the colors will come in handy.

Let's start off with the frontal lobe. This lobe is associated with "intellectual" stuff, like reasoning, emotions, problem-solving, parts of speech, and movement. Found it! Here's an article talking about how we teens act the way we do- it's because our frontal lobes aren't fully connected with the rest of our brain. Doesn't that explain a lot? The next lobe, the white one, is the parietal lobe. This is where we process touch related things, such as pressure and pain. The next lobe is the occipitual lobe, where we process information related to vision. Finally, the green lobe is the temporal lobe, associated with memory and hearing. Of course, your brain is probably snoozing at this point (and I want to get started on my Physics title page) so I'll put more information in The Brain, Part Two. Just keep in mind, though, that the brain is a complicated organ and that these are simply lobes in the brain.

To sum up:

Frontal Lobe: Your reasoning
Parietal Lobe: Your touch center
Occipitual Lobe: Your sight center
Temporal Lobe: Your memory and hearing


Information from: http://faculty.washington.edu/chudler/lobe.html

Pippin's Question Box

The Science of Cooking Teaser

What causes cookies to burn? Best

Guesses on the new (upcoming) theme?