Activity Overview
Students determine how incline affects speed. They will communicate their results graphically.
Before the Activity
Take students out to the playground and ask for four volunteers to sit on the swings. Then ask for four volunteers to push them. Have the four volunteers who are pushing the students to pull the students back at various lengths (for example, 1 foot, 2 feet, 3 feet, 4 feet). Ask the rest of the class to determine which student goes faster and swings the longest and how long it takes that student to stop. Ask students to think about why this happens as they go back into the classroom.
Divide the class into 4-5 work groups.
During the Activity
Explain that we are going to measure how incline affects speed. We are going to do this by measuring how far and how long it takes for a small marble to travel down various inclines. Each group will complete each trial 3 times (triangulation) and take the mean time and distance.
Tell students that they will be measuring the distance and time at the incline of 2, 4, 7, and 10 books. One person in the group should measure the distance; one should keep time; one should roll the marble; two should do calculations. Roles should rotate with each increase in incline.
Instruct students to make a prediction with their group about which height the marble will go the fastest and at which height will it go the slowest.
Experiment and conduct trials!!!
After the Activity
After students have finished all trials and have calculated average time (seconds) and distance (cm), have them sit in their groups and explain what communication is (communicating results using graphs or tables to make it easier to determine results). Hand each person graph paper and explain that students can make either a bar graph or line graph. They need to make a rough draft so that when they do a computerized graph they will have an idea of what it should look like. Give out a TI-73 Explorer(tm) to each group after the rough draft is completed and show them how to hook it up and use it.