Ball Rolling Down an Incline Lab

In this lab, students are asked to identify factors which might effect the ball rolling down a ramp. Once these factors are determined, students set up a variety of tracks/ramps to study the motion of various types of ball.

A simple track can even be made from metal shelving braces as shown above.

 

Materials

1 - Ramp
1 - steel or wood ball
2 - photogates
1 - dual photogate adapter
1 - CBL
1 - TI-82 or 83 calculator.

Two photogates are used with a program are connected through a dual photogate adapter to Channel 1 of the CBL. The program GATE measures the time for an object to pass between the two photogates. The elapsed time is displayed on the calculator. These programs are available as gate.83p. Downloading and operating instructions are available. The program LINCK needs to be on the calculator for the program to run properly.

Students record the type of ball, mass of the ball, and the angle of the ramp.

The angle of the ramp is calculated by measuring a length of ramp along with the height of the ramp. An inverse trig function is used to determine the angle from this ratio.

Students collect data for a variety of distances between the two photogates along the ramp. The ball should be released in the same position and manner each time.

A board clamped to the table is a good way to keep balls from rolling all over the lab. Note one student is entering the data into the list while the others record the data.

Data is entered into the lists of the calculator. The view above shows the distance in cm in L1 and the time (sec) in L2. The user will graph time on the x-axis and distance on the y-axis. The student above set up a stat plot on L2, L1 as shown in the image below.

The image above also shows a regression equation. Since the data was graphed in L2 and L1, the regression line would appear as QuadReg L2, L1 instead of the usual QuadReg L1, L2. Twice the value of the quadratic regression "a" is equal to the acceleration.

This is an example of a graph which does not linearize well. More information on linearization and analyzing this lab is available in a separate section.

If you are an educator or interested in this activity and wish to have more information, send an e-mail to jrynear@lps.org or jwelker@lps.org.
 
© 2004-2008, Jerel L. Welker
Page Updated: August 19, 2008