Ramp Lab

Lincoln High School has taught a precalculus/physics course which matches the concepts taught in precalculus with those taught in physics. As a part of this course, technology is used to record and analyze data. This page features a ramp lab which is used to calculate the distance a ball will land from a table when rolled down a ramp.

The TI-82/83version of the programs are available as generic.83p for Macintosh and Windows Graph Links. Web documentation for the other programs in this group will becoming soon. Please direct comments/questions to jwelker@lps.org.

Setup

An inclined ramp is placed on a table. A motion detector is placed in a direct horizontal line with the ramp at a distance 0.5 meters or greater from the end of the ramp.

Collecting Data

Run the TI program GENCHOOS. (The program LINKCK must also be on the calcultor for the program to run.) Select the Sonic port. Enter the number of points to be collected, and the time between points as .03. Release the ball down the ramp. When the ball is approximately halfway down the ramp, press [ENTER] to begin collecting data.

When the sampling has been completed, a message will appear instructing you to select the left and right bounds using the cursor. Press [ENTER] to display the graph. The graph will appear similar to Figure 1.

Distance from the motion detector is graphed on the y-axis while the time is displayed on the x-axis. The horizontal line at the start of the graph is the distance from the motion detector to the base of the ramp. The line angling downward is the position of the ball vs. time as the ball leaves the ramp. When the ball drops out of the range of the motion detector, the detector once again measures the distance to the end of the ramp. The portion of the graph to be selected is the part of the graph sloping downward. Use the cursor keys to move the cursor to the first point (Left Bound) where the ball dropped off of the edge of the table as shown in Figure 2.

Press [ENTER] after the cursor has been positioned properly. A vertical line will appear through the point on the left bound as shown in Figure 3.

Position the cursor over the position of the boundary point on the right side of the selected region as shown in Figure 4.

Press [ENTER] and the calculator will draw the vertical line through this point and automatically select the points from the left bound to the right bound and transfer them to L3 and L4. The graph of these points appears in a new graphing window as shown in Figure 5.

At this time, the program has been complete executed. Analyzing the data is up to the student using the method chosen by the instructor.

Since the data appears to be linear, the slope of the line ( distance/time) will be velocity.

General Comments

As the diameter of the ball increases, the data will become "rounded" at the ends of the sloping segment. This results from the wave ball bouncing off of the ball at a postion other than the diameter. Therefore, points towards the center of the sloping line will normally yield better results.

The GENCHOOSE program can be used with any autoident probe plugged into channel one. The user can select the number of data points and the time between the data points.

Probe	# of Points	Time
Motion	99	0.02 to ?? sec
Sound	50	0.0002 sec
Light	99	0.00025 sec

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.