IMG_3519We started class by reviewing the first two of Newton’s laws and then talked about the 3rd law – For every action there is an equal and opposite reaction.  If you exert a force on a box, it exerts an equal and opposite force on you.  The lab we did was Lab #6 Rocket Science in Real Science Odyssey Physics.  Basically the students blew up balloons of various shapes and sizes and measured their length or width and then taped them to  a straw.  The straw had a string going through it and was stretched across the room, about 6 meters.  When they let go of the balloon the air would rush out, exerting a force on the balloon that would make it travel along the string.  They spent a good hour doing this and found the more air they put in the balloons the further they would go.  They also found out that water balloons (filled with air)  worked pretty good for this experiment, they were small but traveled a pretty good distance since they were lighter (smaller mass, greater acceleration with a similar force).   To make this lab easier we marked the string ahead of time so the kids just had to count off the marks to find how many meters their balloon traveled. The string had orange marks for meters and blue marks every 10 cm.  It would have taken forever if they had to use meter sticks to measure the string everytime. Here’s a video from one of the data runs.

After they took all their data we talked about the results, answering the questions on the lab handout and then watched the following videos from Veritasium.

I didn’t get to show this TedEd video in class but it summarizes Newton’s laws nicely.