BAM - Periodic Motion

Here is a brief video giving some guidance about the B assignment for periodic motion, in particular question 3.

   

Although this is a repost from my twitter stream, it illustrates the difference in period between pendulums in a beautiful way.

This professor helps to explain resonance and then gives a wonderful simple demonstration. He does some calculation practice for pendulums first as well. Note that in his calculations he is solving for FREQUENCY instead of PERIOD. This means that his formula is flipped upside down compared to ours. The demo he uses is a great illustration of resonance!

Behold the power of resonance! This is video of the Tacoma-Narrows bridge from the 1940's. Every object (pendulum, rocking chair, slinky, even bridge!) has a natural frequency, or rate at which it prefers to vibrate. If you help push it just right (resonance) you can get an effect like this.

Roller Coaster Design

These three videos were created by a mechanical engineer working with the Skate Park simulation to help demonstrate some of the features that might be helpful for your design.

Design Help

Analysis Help

Incorporation of Friction Help

Niagara Falls

Over Christmas break Mrs. Quinn and I went on a road trip that took us into Canada and by Niagara Falls. I have never been before and was blown away by the magnitude of it all. Here is a picture I took from the room that we stayed at:

To the far left are the American falls and to the right is just a small portion of Horseshoe Falls on the Canadian side. I had seen them in pictures before but never up close. Horseshoe Falls in massive, unbelievably massive. Here is a short video of Mrs. Quinn and I standing right by the edge on December 26th.

We eventually made our way down behind the falls into a small tunnel that had posters talking about some of the details about how the falls had changed over time, famous visitors, and how much water actually goes over each minute. I took these two pictures for you guys because they have interesting information about the falls:

 It seems that over a century ago other visitors to the falls realized that not only were the falls beautiful to look at, but they were incredibly powerful. They developed ways to take energy from the falls and use it to power local towns. In fact, when I was there a new tunnel was being built to make the power plant even better and more efficient. In total 750,000 gallons of water go over the falls every second! 1 gallon is 0.0037854 cubic meters and 1 cubic meter of water is 1000 kg. With that information could you determine how powerful the falls are? Since there is a restriction as to how much water could be generated for power, what is the maximum amount of power that is actually generated? For comparison sake the maximum output of an 18-wheeler is 450 kW.

Niagara Falls is famous for daredevils going over in barrels. What I found out when I was there is that the first person to ever attempt/survive this feat was a woman name Anne Taylor, pictured below. I was also amazed to find out that she 63 when she made the attempt!

 Based on the height of the falls, can you determine how fast she must have been moving when she landed? Anne survived,but many others have not been so fortunate. In fact, since 1850 an estimated 5,000 bodies have been found at the bottom of the falls. The falls are another great example of the power, beauty, and potential danger of the natural world.