Drop Tube

Author: Joel Brock and Sue Henne Date Created: 2006

Subject: Scientific Process, Physics

Level: 4th grade Standards: New York State- Intermediate Science (www.emsc.nysed.gov/ciai/)

Standard 1- Analysis, Inquiry and Design Standard 4- The Physical Setting Standard 6- Interconnectedness: Common Themes Standard 7- Interdisciplinary Problem Solving Schedule: One 40-minute class period

Objectives:

Be informally introduced to the concept of momentum and how it relates to force. Practice the scientific method through accurate data collection, graphing, and making predictions.

Students will:

• Take measurements

• Use graphs and tables to record data

• Make estimations

• Students will use collected data to make scientific predictions

• Replicate their results for accuracy

• Have a hands-on experience related to force

• Quantify their intuition about simple forces

Vocabulary:

Scientific Method Estimate Predict

Accuracy Replication Variable

Materials:

For Each Pair: Tube Foam† Set of metal cubes Spring scale Ruler* String Stickers

For Each Class: One sponge One lead brick For Each Student: Activity Sheet 1: Simple Forces

*Provided by the teacher †

Foam #22 is the standard used for this lesson, other foams are of increasing density as reflected by their number

Safety:

Do not remove covering from lead cubes.

Science Content:

This lesson builds upon students’ prior knowledge and intuition about motion, momentum, and force. These concepts are not introduced formally; however, students are encouraged to think about these concepts informally as they complete the activity.

The focus of this lesson is on the scientific process and quantifying students’ intuitions. The graphs and charts used by the students as they work through the activity require them to record data accurately and make predictions based on their findings. Students must also be aware of human error and make sure they are measuring only one variable.

Preparation:

1. Photocopy print materials (Activity Sheet 1) for each student. 2. Materials should be divided based on the number of student pairs/groups.

Drop Tube - 2 –

Classroom Procedure:

Engage (Time: 5 mins)

Demonstrate the relationship between weight and momentum by asking students which brick they would rather have dropped onto their open hand: the sponge ‘brick’ or the lead brick. Explain the drop tube is a too used for measuring the same effect.

Explore (Time: 25 mins)

Demonstrate how to use the spring scale, remind students to zero the scale before use for more accurate results. Demonstrate how to load the foam into the drop tube. Explain that students will need to be conscious of the potential for human error (ie: making certain the foam is level with the bottom of the tube before each trial). Show students a copy of the activity sheets and explain that all instructions can be found in their packets. Emphasize the importance of precision and measurement when recording data. Remind students to be consistent in their measurements and that all the scales need to be zeroed prior to weighing any of the blocks. Make sure that students label both x- and y-axes on all graphs. (Note: If working with younger kids, help them label the graph axes on the Activity Sheets.) Distribute all materials necessary for the activity (including Activity Sheet 1: Simple Forces). Before they begin the activity, remind students to leave the tape on the lead block. Assist as necessary.

Explain (Time: 10 mins)

After completing the activity, encourage students to share their successes or failures, or any problems they may have encountered during the assignment. Allow time for questions.

Drop Tube - 3 –

Assessment:

The following rubric can be used to assess students during each part of the activity. The term “expectations” here refers to the content, process and attitudinal goals for this activity. Evidence for understanding may be in the form of oral as well as written communication, both with the teacher as well as observed communication with other students. Specifics are listed in the table below.

1= exceeds expectations 2= meets expectations consistently 3= meets expectations occasionally 4= not meeting expectations

Engage Explore Explain 1 Shows leadership in the discussion and an understanding of the concept of momentum.

Completes work accurately while providing an explanation for what is observed. Works very well with partner.

Provides and in-depth explanation of findings. Fills out worksheet clearly.

2 Participates in the

discussion and shows some understanding of the concept of momentum.

Completes work accurately and works cooperatively with partner.

Provides clear explanation of findings. Fills out worksheet clearly.

3 Contributes to the

discussion, but shows little understanding.

Works cooperatively with partner, but makes some mistakes with the procedure.

Provides a limited explanation of findings. Fills out some of the worksheet. 4 Does not participate in

discussion. Shows no understanding.

Has trouble working with partner. Does little to complete the procedure.

Is not clear in explanation of findings. Does not fill out worksheet.

Extension Activities:

• Students could experiment with dropping different materials and measuring their results.

• Students might brainstorm other ways of measuring the same effect.

• Students can experiment with foam of different densities and measure their results.

Safety:

•

Make sure the students do not remove the covering from the lead cubes.

Drop Tube - 4 –