In this activity, students examine how moving a weight up along a board affects the downward force on the board. They explore how children with different weights can be balanced on a seesaw.

Before the Activity

Position the scale and the block far enough apart so that the wooden plank is supported on one end by the scale and the other end by the block

Starting at the edge of the scale, place marks at 10-cm increments on the wooden plank

Set up the calculator for data collection using the procedure described in the attached Appendix PDF file

See the attached PDF file for detailed instructions for this activity

Print pages 25 - 37 from the attached PDF file for your class

During the Activity

Distribute the pages to the class.

Follow the Activity procedures:

Place books at the 0 cm mark on the plank and record the weight

Move the books to the 10 cm mark and record the weight

Continue to move the books away from the scale in 10-cm increments and record weights

Enter the data of distance and weight as a list

Use this data to graph a scatter plot

Visually estimate the trend line and find the line that contains as many points as possible

Determine an equation for a trend line for the data, calculate the slope, and graph the trend line

Find the weight of objects placed at different distances from the scale

Find the distance from the scale given the object's weight shown on the scale

Find a linear equation for the data

View the graph of the best fit line

Use the linear regression model, find weights at different distances, and find the distance given the weight

After the Activity

Students will complete the Data Collection and Analysis page and answer questions.

Review student results:

As a class, discuss questions that appeared to be more challenging