Heat Transfer

Heat Transfer Experiment Reflection

After reflecting on the results of the heat transfer experiment that tested various materials to find the best insulator, I found that conduction and convection were taking place.  The ceramic mug that was used to hold the water became warm through conduction.  The materials I tested as insulators were: a thick plastic lid, a piece of wood, a piece of latex, a paper plate, a cotton cloth, and aluminum foil.  The data showed that after forty minutes the mug that was covered with the aluminum foil was the warmest.  Convection currents within the liquid were cooling the liquid as the heat was moving from the warmer object to a cooler one. 

If I were to test more materials to find the best insulator I would test: styrofoam,  plastic wrap, a piece of thermal underwear and a piece of notebook paper.  I have chosen these objects because through researching I have found that materials that make good insulators are materials that contain pockets of trapped air like the feathers on a bird.  My prediction for the best insulator in this group of materials is the styrofoam.

If I were to test liquids other than water, I would test syrup and soda.  I would test these liquids because I am curious to see if the density of the liquid affects the rate of cooling. 

Guided Inquiry

Question and Procedure:

The guided inquiry question that my son and I chose to investigate was – How do different surfaces affect the momentum of marbles?  The first piece of information that we needed to find in order to answer the question was – What is momentum?  We found that momentum is defined as the product of the mass of an object and its velocity.  Velocity is the speed and direction of an object and speed is a measure of how fast you are moving and is defined as distance per unit of time (Tillery, Enger, Ross, 2008).  Prior to setting up our experiment, we needed to identify and locate different types of surfaces to test.  We tested three different surfaces with two marbles of different masses.  We decided that we needed variables that would remain constant for each test.  We decided that the marbles, the distance the marbles would travel, and the height of the ramp were the variables that would remain constant.  We located the different types of surfaces we were going to test:  a hardwood floor, a short nylon carpet and a thick shag carpet.  We measured the mass of each of the marbles.  One marble was twenty one grams and the other was eight and one tenth grams.  We set up a ramp that was thirty four inches long and thirteen and a half inches high.  We measured one hundred and twenty five centimeters on the first surface that we were going to test; the hardwood floor.  Prior to our test, we predicted that the marble would roll the fastest on the hardwood floor because the surface was smooth and there would be little rolling friction between the marble and the floor.  We then let each of the marbles roll from the top of the ramp onto the hardwood floor and timed how long it took to travel forty nine inches.  We followed the same procedure for each surface, ran three trials on each and recorded the data.  We found that the marble with the smaller mass traveled faster on the hardwood floor and the shorter shag carpet.  We found that neither of the marbles would travel the entire distance on the thick shag carpet, but the marble with the larger mass traveled a farther distance before stopping.  However, we discovered that after calculating the momentum of both marbles, that the marble with the greater mass had greater momentum. 

Successes:

This inquiry worked well with within a small group.  We were able to discuss our investigation and the results we were observing.  We were able to collect and record data with greater ease. 

Modifications:

Changes that I would make to this activity would include a larger variety of surfaces and the angle of the slope.

Application:

I would incorporate this guided activity in my classroom to teach mometum as a structured inquiry lesson.  I would incorporate changing the angle of the slope on the various surfaces to increase or decrease momentum.  This lesson would reinforce Newton's Laws of Motion.