Tides

This video is a time lapse of the Bay of Fundy's tides. Although this is an extreme case of high and low tides, it clearly shows the difference between high and low tides.
The reason that tides occur is because of the moons pull on the earth. Tides on opposite sides of the earth are always the same. If you picture the globe, the left and right sides would have high tides and the top and bottom would have low tides or vice versa. This happens because of the difference in force felt by each side. For example, one side of the earth, lets call it side A, is adjacent to the moon and the other side of the earth, lets call it side B, is opposite to the first side. Side A would be a shorter distance away from the moon and because of the formula F=m1m2/d^2, it would have a large net force. Therefore, side B would be a larger distance away from the moon and have a smaller net force. The moon would also have a pull on the center of the earth which would be less than the force of side A, but greater than the force of side B. For example, the force of side A is 15, side B is 5 and the middle is 10. As stated earlier, the difference in force felt by each side is what makes opposing sides of the earth have equal tides. To find this difference, we subtract 10, the middle number from 15 and 5, each side. When doing this, we get 5 and -5. This means that we have a force of 5 pulling to the right and to the left. This creates a tidal bulge. Without a difference in force, we would get a net force of 0, creating no tides at all.  High and low tides alternate and occur about every 6 hours with each occurring 2 times a day.  High and low tides occur every 6 hours because of the time it takes the moon to orbit earth. There are also tides called spring tides and neap tides. Spring tides occur when the sun, earth, and moon are lined up either sun, moon, earth or sun, earth, moon. When this happens, there is either a full moon or a new moon and the tides are unusually high and unusually low. Neap tides occur when the sun, moon, and earth do not line up either sun, earth, and moon above or below the globe. When this happens there is a half moon and the difference between the tides are unusually low.
In the summer, my family likes to visit our friends in Rhode Island. They own a house on the Sakonnet beach. Here is a link to a Sakonnet tide chart: http://ri.usharbors.com/monthly-tides/Rhode%20Island/Sakonnet . Right now, as I am writing this post at 8:50 pm, the beach is in-between high and low tides and turning into a high tide and experiencing neap tides. 

Newtons 3rd Law Resource

Despite the minimal animation, I think this video does a good job simply and clearly explaining Newtons 3rd Law. It helps to explain action and reaction pairs and clearly states the law. I found the bicycle example most helpful because it showed a real life application of the law.