Insulation

This week I conducted an experiment on how well items insulate heat.  As we know hot molecules are in constant search for colder ones until an equilibrium is reached at what we call room temperature (Keenan Fellows, 2013).  The hot air rises out from the water and cold air storms in, this is called convection.  One can feel this first hand when touching something metal in the room.  Because metal is such a good conductor of heat the heat from ones fingertips is drawn out and into the chair.  The release of heat in ones hand makes the object appear to feel cold, even though it is the same temperature as every other object in the room (Tillery, Enger, & Ross, 2008,). 
 Knowing that metal is a good conductor, I knew it would be a very poor insulator.  I tried to use more materials that resembled a houses insulation like fiberglass.  Something that had small pores but did not feel cold to the touch, like a shirt.  However, I stretched the shirt out and with too big of holes it was not a good insulator.  I would like to try to put a shirt loosely over the mug of hot water just as the shirt hangs loosely over us, keeping us warm.

I would also like to try other items out in the mug instead of water.  It would be interesting to see if a denser subject would lose its heat slower than water.  thick syrup or thin watery spaghetti sauce would be interesting to test.  This would make the project more engaging for students as I would want to apply it to their lunches.  How can we keep moms chicken noodle soup warm until lunch?  I would want students to create a lunch box that will be able to keep something warm for up to two hours.

I would want students to not only explore but to engineer a design using the concepts gathered.  I would want them to be able to tell me why a material is a good conductor or a good insulator.   I learned that a good conducer is often a poor insulator.

Pendulum in Motion

Dealing with a 4/5-combo class this year directly correlated me with a pendulum in motion.  I felt one with the experiment as I constantly feel like a pendulum myself.  To test the theory that momentum = mass x velocity, I used string, 3 weights of different masses, and a hook in my ceiling.  Since I did not have a ruler on me, I measured the string from elbow to middle finger, and the dropping point was a Elbow to fist from the ceiling.  I had to be creative.  Luckily in school I found that taping the string to the edge of a desk works perfectly while using a yard stick to keep an accurate dropping point would suffice.

My results are listed below and were on par with what I expected.  I knew that a heavier mass would create more momentum.  What I would want to know and test with the students is to find graph the curve to be able to predict what the resting point would be from multiple weights or string lengths.

The experiment went well but it was a lot of waiting time.  I may predict boredom will set in with my type of students.  Not only that but the accuracy of knowing when does is the object finally at rest.  Towards the end the weight tends to circle around in motion for a few minutes allowing students to grow impatient.

To bring technology in I would want groups to test multiple scenarios, then as a class graph it on Excel and see if we could predict what would happen if we changed the variable.  To make the experiment more exciting I would want to keep the kids busy while waiting for the pendulum to come to a rest, or possibly give them shorter string than what I used.

For students I would want them to learn how to graph data, interpret data to infer predictable outcomes, that gravity is the friction in play, and understand Newtons law that an object in motion will stay in motion unless a force is applied.

Before testing this experiment with my class, I would love to hear from you what to watch out for, and how to better this experiment to keep them busy while watching the pendulum.  in which ways could I make this more exciting?  possibly using action figures as the mass?