December 20

# The Magic of Light

the reason why the arrow is reversed is because of a combination of refractions. the light travels and finds its way to the front of the beaker and the light refracts off the glass into the water into the other side of the beaker and then finally to the arrow which makes it look inverted

December 11

# Wave Interference

Constructive waves are waves that are moving towards each other in the same direction. when they meet somewhere in the middle the two amplitudes conjoin and it makes one big amplitude and after they pass they go back to the way they were before

Destructive waves are waves that are moving towards each other but one amplitude is opposite the other.  When they meet the amplitudes cancel each other out then after they pass they go to the way they were before

December 6

# Archimedes Challenge 2017

Where was it invented? : in Syracuse, Greece

Who invented it? : Dionysius the Elder

Why was it invented? : Back in the day people were building their castle walls higher and weaponry could not take them down so they invented the catapult which could break down these walls

Short term implications? : it was a major advance in weaponry at the moment because no one had seen anything like it and it was shown effective.

Long term implications? : we don’t really use catapults anymore because of gun powder and missiles now and there aren’t as many castle walls to be torn down

here are some pictures of the finished project and the process it took to build it.

the physics behind it: for ours all you have to do is apply force to the arm of the machine and the tension of the object it wants to go back in place so when it snaps back in place the object in the little cup will go flying because of inertia

our process of building the machine: the first day was pretty tedious with all the measurements and making sure everything is equal so that our catapult and then it came to cutting the pieces out and it had to go through the table saw more than once for perfection. Day 2, we started assembling and hot gluing the wood together but we didn’t have clamps so what we did is we hot glued and then we taped it really tight together so it had no wiggle room. after a while we eventually had to shoot some staples in there for extra stability. Day 3, it came to figuring out the arm situation and how much pressure you can put on it, I had to test that out and I snapped it almost immediately so we had to reinforce it with two other small pieces of wood. Day 4, it came time to test the machine out and it turned out alright, the ball traveled more vertically than horizontally but that’s okay too.