Thursday: M&Ms

Recently I tried some of the new M&M flavors, so I thought I'd report to you what I thought of them.

First: Pretzel M&Ms. I thought they could have used a higher chocolate to pretzel ratio. While I might eat them again, they weren't my favorites.

Second: Coconut M&Ms. I really liked these. They were coconut flavored but not too strong. And they had some cool extra designs on the Ms.

Wednesday: back to work

Ah, after a lovely vacation I had to go back to work today. Really, it wasn't that much fun.

I thought several times that maybe I should have just taken the whole week off. :)

NYC: Day3

Today we went on a boat tour around the island. It was very nice to see all the landmarks without having to walk. I was doing ok, but my legs were getting a little sore.

NYC: Day2

We started the day by taking a stroll through Central Park.

Notice how well Ben and I match? He wore that shirt just for me.


Hanneke was able to join us! We usually manage to miss each other over Christmas, so it was really nice to be able to see her again.
We took a whirlwind tour through the American Museum of History. I'd love to come back with more time.

I'm kind of proud as how I managed to get us in this photo on the glass.

In the evening we saw Blue Man Group. It was great. It was much more of a comedy routine than I was expecting, but there was still a lot of percussion.

(Image courtesy BlueManGroup)

NYC: Day1

We started out the day with a delicious strawberry pie for breakfast.

Phew! We made it to NYC without too many issues.

After some walking around to see the sights near our hotel, we finally found something the guys would get their pictures taken with.

We went to a Brazilian steakhouse for dinner. It was a lot of fun, and really interesting to try all sorts of meat. My least favorite was the chicken, and my most favorite was the flank steak. I also loved the sides - mashed potatoes, fried bananas, and a salad bar that had more than lettuce. Laura amazed us all by eating a ton of food; her favorite were the ribs.

We ended the day by going up 30 Rock and seeing the skyline at night.

Monday: dragons

We made it back from NYC! Pictures and such to follow, probably tomorrow. It was a good trip.

I'm currently reading Joust by Mercedes Lackey. I've read it a few times before, but it always makes me want a dragon. I think I want a white one because Flurry is white. I've asked her a few times if she wants to become a dragon, but the answer always seems to be "no."

Floating subs

Why do submarines float (and sink)? It's all a matter of controlling the sub's density. If the submarine is less dense than water, it will float. If it is more dense, it will sink. So let's start by looking at density. In words, density is how much stuff is in a certain amount of volume. Mathematically, density is as follows:

(Side note: if you were to measure density on the Moon, another planet, or deep in the ocean, you'd have to worry about the difference between weight and mass. Fortunately, for most people reading this post weight and mass are approximatively equivalent. For more information, check out this link.)

We're also in luck...water has a very easy density to remember: 1000 kg/m^3. Ocean water is slightly different due to it's salt content, but for our purposes we're just going to ignore some of those subtle nuisances.

When a submarine is floating on the water, its ballast tanks are filled with air. So let's pretend the bottle below is a submarine with air-filled ballast tanks and measure it's weight.

Next the volume of the bottle needs to be deterimed. Normally this would be done by sticking the whole bottle into a graduated cylinder filled with water, but I do not have one. So I estimated the number of teaspoons that the bottle held with a measuring cup. There were about 78 teaspoons.

So now that we've found the weight and volume (and converted them to practical units), we can find the density of the empty bottle.

So here's the big question...will the bottle float?? Do you remember what we said about density up above?

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It floats!

It floats because the density of the bottle (601.5 kg/m^3) is less than water (1000 kg/m^3).

Next let's fill the bottle with blue water and see what happens. We already know the volume, but we need to find the new weight.

With the new weight we can find the density of the bottle filled with blue water:

So, is the bottle with water going to float?

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No!

The bottle sank because its density of 1573 kg/m^3 is more than that of water.

Can you figure out how full the bottle should be so that it will hover in the water?

Here are some more interesting links:

How Stuff Works

MSI learning lab