The question I chose to investigate this week was - Which pendulum will come to rest more quickly—a lighter pendulum or heavier pendulum? In order to find an answer to this question, I designed a test using the following materials:
*1 1/2 inch washer
* 1/2 inch washer
*2 pieces of string of equal length
*tape
First, I thread a piece of string through the larger washer and tied it to the towel rack in my bathroom (yes, this may seem like an odd choice - but it worked.) :) Then, I extended the string all the way to the bar and let it go. As I let go of the washer I began my timer. I did this three times and recorded the results. I repeated these steps with the smaller washer as well. The larger washer took more than twice as long to come to rest as the smaller one.
One challenge I had with this activity was identifying when the pendulum actually stopped moving. It seems like it moved ever-so-slightly for a VERY long time. I tried to stay very still so that I would not produce any sort of air currents that would cause the pendulum to continue moving. I can predict that this may be a challenge for my third graders as well.
If I present this inquiry lesson to my students, I will change a few things. First, I will let them work with a partner to construct a holder for the pendulum. Having five boys of my own, I have plenty of Lego's and building toys that they can use. Also, I had the idea to extend the activity by taking them to the playground and using the swing as a pendulum. That way, they can connect the lesson to something they use every day.
I really enjoyed this week's guided inquiry experience. As I continue to work through these courses, I feel like I am becoming more and more comfortable with this level of inquiry.
Lisa,
ReplyDeleteI had the same problem as you trying to patient enough until the pendulum came to a complete stop. I used the shadow on the wall to help me determine when it came to a stop because I think the light reflecting off of the washer sometimes gave the impression of movement. Do you think it would have been easier with a bob that was not metal or shiny?
-Julie
Lisa,
ReplyDeleteI did not do this experiment, however, I can invision the problem of not knowing when the pendulum stopped moving. This can be a problem for any student of any age, even us! It might be a good idea to go over this with your students before hand as a reminder. Also, everyone sees things differently, so that is also something that might be tough.
I feel the same way about this course. The more we do it, the more comfortable I feel. Which makes sense to me when we are talking about introducing this to our students, they will get better and more comfortable with practice.
Great post!
Lisa,
ReplyDeleteI also had the problem of figuring out when the pendulum stopped. I had both pendulums going at the same time so that I could see the difference in their swings at the same time. I like the idea of having your students come up with a holder for the pendulum. I also had difficulty finding one and it would be a good inquiry for the.
Lisa,
ReplyDeleteI have been conducting this experiment for several years now. My inquiry lesson would be presented a little different though. My students would investigate does the weight or length of a pendulum affect how many times it will swing? My solution to the pendulum actually stopping would be to use a timer. We would count to see how many times the pendulum would swing in a minute.
I love conducting this investigation because the results are very shocking to many of my students.