Motion of Cars Investigation - 9/21/2011

We started off class by introducing a investigation focused on the motion produced by a battery operated car in comparison to the motion produced by a pull-back car. More specifically, the lab requires us to determine if each car produces uniform motion (where the object moves at a constant speed and in an unchanging direction), or non-uniform motion (where the object has an inconsistent speed or a changing direction). We will do this by examing the marks made by the ticker timer as the cars as pull the paper through the timer.


With Daegan and Unger to assist him, Mr. Banow ran through the procedure involved with collecting data for the investigation. Next, in groups of three we began collecting the appropriate data.

Procedure:
First, we had to calculate the number of marks that indicate a time lapse of .10 seconds. Because we know the frequency that we receive is 60. Hz, we can perform the following calculation:

P=1/f
P=1/60. Hz = 0.016666666
0.016666666 x 6 dot intervals = 0.10


Therefore, in a time lapse of .10 seconds, the ticker tape produces 7 marks, and 6 dot intervals.

• Then, in groups of three, we cut a piece of recording timer tape to about 2 m long, and plugged in the recording timer and placed it on one end of the table.


• We inserted the timer tape into the timer, and used masking tape to secure the recording tape to the back of the pull-back car.


• One group member held the loose end of the recording tape, ensuring it passed through the timer correctly, while the second person was responsible for turning the recording timer on, and the third group member was responsible for winding up the pull-back car.


• Once the tape had passed through the timer, the tape was detatched from the car and the same process was done with the battery operated car.


• Each group then began to analyze the markings on each piece of tape, in order to determine what kind of motion each car had.

Lindsey is next.