Pendulums

What is your personal experience with swinging on anything like a trapeze?

As a kid, I swung on my school's swings a lot. It was my friend and I's favorite thing to do at school. We always had competitions to see who could swing the highest and who could jump off of the swing the highest and land on our feet. Was it dangerous? Oh yeah. Were we asked to stop? Everyday. Did we do it anyway? Of course.

What applications to “real life” do swinging objects have?

In a general sense, we are all in a constant state of “swinging like a trapeze”. The reason I say this is because we do something, something happens, and we do another thing. We are constantly moving in some direction that affects how we move. Things in our lives such as family, friends, education, and activities are always affecting us in a way that forces us to be “swinging back-and-forth”.

Most people predict these three variables are the most important: angle of release, weight and/or length of pendulum.  Which variable(s) or combination of variables do you believe will have the most impact on the frequency of the swings of a pendulum? List them out and then explain why you think that. (this is the same as the formative assessment but this way we can share with our peers and will drive our investigation).

In terms of a pendulum, I believe that the angle of release, weight and length of a pendulum all work together to make the pendulum work effectively. I believe that none of the above factors are more effective than another.

What understanding or ideas do you have about the science of back-and-forth swinging objects?

All i know about the science of back-and-forth swinging objects is that if you drop from angle A, it will not get back to that angle until you restart the process. Slowly but surely, the pendulum will stop.

To test what factors affect the swing of a pendulum, my partners and I tested how angle, weight, and angle plus weight affects the frequency of the pendulum. Each trial was timed for 15 seconds. Here are the results of each factor after four trials:

Variable(s)	Trial 1	Trial 2	Trial 3	Trial 4	Mean
Angle/Weight	70-1: 9.25 swings	90-2: 9 swings	80-3: 9.25 swings	60-4: 9.25 swings	9.19 swings
Angle (degrees)	70: 10 swings	90: 9 swings	80: 9 swings	60: 9 swings	9.25 swings
Weight (# washers; 80 degrees)	1: 9 swings	2: 9.5 swings	3: 9.25 swings	4: 9 swings	9.19 swings

Questions to consider: if there was a significant amount of weight added to the pendulum, how much would that weight affect the amount of time it takes for the pendulum to complete a full cycle?