Pick Peat!

A “megapixel” is how the resolution of digital cameras is measured.  Simply put, the more megapixels a camera has, the more detail it can capture in an image.

More specifically, a megapixel is a million light sensors.  In a digital camera, these light sensors are arranged in a grid, and each is filtered to receive either red, blue, or green light.  In an eight megapixel camera, you’ll have eight million individual light sensors.  It’s pretty amazing that we can fit all that on a chip the size of your thumbnail!

Now lets consider printing your photographs.  To get a crisp picture that isn’t blocky or blurry, you want an image resolution of at least 300 dots per inch:  that’s about the resolution of what you see in a nice magazine.  Since a dot in your print represents a pixel in your photo, you can then calculate the size of the image required for a certain sized print.

Here’s an example:  Lets say you want to print a 5 by 7 inch photo for a contest application.  To get a sharp photo at 300 dots per inch, that means you need an image that’s at least 1500 by 2100 pixels (thats 5 inches times 300 pixels, by 7 inches times 300 pixels).  To determine the number of pixels required to produce that image, we simply multiply the width by the height to get 3,150,000.  That’s a little more than 3.1 million pixels … or 3.1 megapixels!

If you want to see something pretty amazing, check out the gigapixel photos (that’s billions of pixels) at www.gigapxl.org.

It doesn’t!

A “corked” bat is a wooden baseball bat with hole drilled into it and filled with cork, superballs, or other light, springy material.  The theory is that the bat becomes lighter, so it can be swung faster, and hit the ball farther.

Drilling out a bat and replacing the innards with something like cork will certainly make the bat lighter, and that means it can be swung faster.  However, the deciding factor of how far the ball goes  is how much energy is delivered to the ball when it’s hit.

To calculate the energy the bat has, you multiply its speed by its mass.  With a corked bat, you’re gaining speed but loosing mass when you make it lighter, so even under the best of circumstances you’ll be launching that ball about the same distance.

That’s one theory, anyway.  The MythBusters actually tested this out in their baseball special, and found that the corked bat significantly reduced the distance a ball could be hit.  

However, there is another reason why players might cork their bats: surface area.  A corked bat stays the same size, but gets lighter.  The bat is easier to control, and retains a large surface area, both of which could improve the chance of hitting a ball and getting on base.

Quick update:  Dane sent over a link to a really great explanation and some fairly detailed research on corked bat performance.  The verdict: corked bats won’t help you put it over the fence.

Another note: Jay asserts a corked bat gives the batter more control, because the bat deforms when it strikes the ball — increasing the size of the contact patch between the baseball and the bat.  More theories?  Send ‘em to peat@peat.org … thanks!

The speed of light is a fun topic.

For starters, the speed of light isn’t constant!  There is a limit to how fast it can go (299,792,458 meters per second in a vacuum), but the observed speed can be changed by what the light is moving through, and changing what exactly you’re measuring.  But, for the sake of brevity, lets focus on the the idea that the speed of light is constant in a vacuum.

First off, the speed of light has been determined to be a constant based on lots, and lots, and lots of experiments.  While the specific results of those experiments have changed over time, they’re all converging on a single value.

Current methods for measuring the speed of light usually have to do with measuring the frequency and wavelengths of lasers.  

Aside from being totally awesome, why lasers?

Lasers are important because they create coherent light waves with a specific frequency — or in other words, the light waves are all synchronized, rising and falling in step with one another.  

Another way to think of it is to think of a stadium packed with people doing a “wave” — although there are tens of thousands of individual people cheering, there’s a pattern to how it flows around the stadium, rather than the chaos of everyone cheering at the same time.

With a coherent light source of a fixed frequency, we can measure two things:  the frequency of the waves, and the length of each wave.  Multiply the two together, and you get how quickly the light is traveling.  Because light of different wavelengths and frequencies all produce the exact same results, we can reasonably conclude that the speed of light in a vacuum is a constant.

The final twist is that scientists have such confidence in the speed of light, they use it to define a meter, rather than the other way around!

“The metre is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.” — Bureau International des Poids et Mesures

So, scientists don’t measure the number of meters the light travels in a second:  they take the distance light travels in a second, divide it by 299,792,458 … and that’s a meter.

… she did!

Thats my wife, and she’s totally awesome.

That’s also a Cubs game.  If there’s any opportunity to mix up the MATM and the Cubs, I’m game!

E stands for energy, m stands for mass, and c stands for the speed of light in a vacuum.  Using the metric system, this can be written out as:

Joules = Kilograms * (Meters per Second)^2

… which works to about 90,000,000,000,000,000 joules per kilogram.  That’s a lot of energy!

But what does it mean?

Here’s where it gets fun.  Since this is an equation, if you add energy, the mass also has to increase.  We can’t really see this in our day to day lives — even the Space Shuttle only gains the mass of a flea after accelerating to it’s top speed of about 18,000 miles per hour.

However, we get to see it very clearly in a particle accelerator!

A particle accelerator takes a proton, and gives it electrical jolts to accelerate it.  Because protons weigh very little, and the jolts contain quite a bit of power, the protons quickly hit the ultimate speed limit:  the speed of light.  Never the less, the accelerator continues to zap the protons, so they increase in mass instead of going faster.

How much mass?

The fine folks at CERN say their accelerator, the Large Hadron Collider, can give a single proton the same amount of momentum as a flying mosquito.  It doesn’t sound like much, but consider that a mosquito has the mass of about 1,500,000,000,000,000,000,000 protons, give or take.

There are finer points to how all this plays out, but that’s the gist:  mass and energy are equivalent.  This elegant little equation, coupled with the relativity theories of the early 1900s, fundamentally changed how we understand the world.

Great stuff!

As of today, there are 473 planets outside of our Solar System, also known as “exoplanets.”

The cool part is that we can’t actually see most of the exoplanets, but we can see stars wobbling in a way that indicates something is orbiting them.  

A good example of this wobble is if you grab a heavy backpack and spin around in circles.  If you’re spinning fast enough, you’ll have to lean back a bit to counteract the weight of the backpack.  In the same fashion, a star will “lean back” a bit to balance a planet orbiting around it.

Astonomers look for this wobble (or “radial velocity”) to find stars that may have planets orbiting them.

When we calculate the mass of the star and the radial velocity, we can figure out how big and far away the planet is.

If you want the cutting edge list of exoplanets (and slightly more technical details on how they’re found), check out http://exoplanet.eu/catalog.php

One of the neat things about the Sun is that it’s not just a simple ball:  it’s more like an onion with lots of layers, rather than a potato that’s just a bunch of potato all the way through.  

The different layers of the Sun provide different functions, starting with the core, which produces all of the energy, on out to the heliosphere, which is basically the Sun’s “exhaust” cloud.  Generally speaking, the layers form based on how hot they are, and how fast they’re moving.

So when we talk about the Sun’s surface, we need to figure out which surface we’re talking about, since each of the layers of the Sun has boundaries with the other layers.  I suspect you’re referring to the surface we’re most familiar with — the bright white orb that has a distinct boundary against the rest of the sky.

That’s the photosphere.  It’s mainly defined as the last layer we can see through, and it’s also the last layer that produces a significant amount of light.  Outside of the photosphere is is the corona (see the picture below), and the heliosphere, which extends to the edge of our Solar System.  We can see through both the corona and the heliosphere, but not the photosphere, so we generally consider that the “surface” of the Sun.

In an ideal world the relationship between a lead-acid battery and a gallon of gasoline is defined by a few thousand pounds of steel, a touch of leather, and about fifteen miles on the highway:

I’m tempted to side with Turgor, because plants are delicious, and I have a keen appreciation for being able to digest ‘em.

On the other hand, if it weren’t for hydraulics, I wouldn’t be able to water the plants or drive to the greenhouse to pick up new ones.

I say they’re both pretty awesome … but I’ll give the nod to Turgor.  My stomach rarely fails me.

Fresh Tomato (c) Darren Hester