Where do you Keep Your LEGOs?

In your LEGO® safe?

You would think that breaking into a Lego safe would just mean taking a few bricks off but this one is quite a bit more complex. The safe weighs 14 pounds for starters. It has a motion detecting alarm so it can’t be moved without alerting people in earshot. The lock require five double digit codes to open it, which results in over 305 billion different combinations.

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The Billy Preston Effect

Will it Go ‘Round in Circles?

Building The Amazing Steam Candle

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This is a variant of the pop-pop engine — if you point the tubes parallel rater than in opposite directions, you’ll get linear propulsion.

At first glance you might think this couldn’t work. Once you hit steady-state, the rate at which water enters and exits the tube has to be equal. Inside the tubes, that means that the momenta must be equal in magnitude, but opposite in direction, meaning no net momentum for the water, and no propulsion for the boat. The effect is a little more subtle — one has to consider what happens at the entrance to the tube. The water exiting will have its velocity vector along the direction of the tube. But the incoming water is drawn from different directions; it only has to have a component of its velocity in the direction of the tube, meaning the ejected water exerts a greater force.

It's a Communist Plot

There were a number of records set at Domino Day 2008.

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I thought the scene of the last 45 seconds or so, showing a field of dominos falling in parallel, was particularly interesting. The curve that defined the leading edge of falling dominos was not a straight line, and it changed shape a little — the speed of propagation through a line of tiles is not constant. With identical tiles it should depend on the spacing, which would dictate the time it takes for one falling tile to hit the next and the speed with which a domino strikes its target. But wile a larger spacing means the tip is moving faster, it also strikes at a lower point, which means it exerts a smaller torque to get the next tile to fall, so it wouldn’t be a simple relationship. You could also change the mass for another variable in the domino wave equation.