GoPro Underwater Challenge - Falling Coins

Created Feb. 7, 2024 by Dennis Roy

GoPro Challenge


Effects of Water Friction (Resistance) on Falling Coins


Description

This project will look at the effects of water resistance on falling coins (a penny, nickel, dime, quarter, half dollar and silver dollar).  We will be dropping in the coins in 4 feet of water to observe the effects.  Students will be hypothesizing what effects the water will have on the coins (i.e. will coins fall straight or flutter), they will predict the order in which the coins will hit the bottom of the pool.  Students will be required to list their reason(s) for the order they chose. Students will be required to do 20 trials (coin drops), film each trial, view in slow motion and record the order in which coins hit bottom of pool for each trial in a data table they create.

Learning Goal

  • Students will learn to remove as many variables as possible from the coin drops to ensure consistency in their trials.

  • Students will improve their ability to reason by predicting the order in which coins will hit the bottom of the pool based on their previous knowledge of gravity and air resistance.

  • Students will improve on their communication skills by trying to convince one another that why they think their predictions are correct.

  • Consistent data taking and observing

Depth of Knowledge

Students will be engaged to think critically by trying to determine if the effects of water friction on falling coins is similar to the effects of air friction on falling coins.   As mentioned above the students will be charged with constructing an argument to defend their prediction for the order in which the coins will hit the bottom of the pool.

Standards

Common Core Standards that will be met

Student Levels & Needs

This project can be tailored to work for grades 4 through 12, we used 6th grade for our lesson.

Teacher Preparation

Teacher will need to know the basics of air resistance on falling objects as well as having a strong knowledge of how to teach students to set up an experiment correctly to eliminate variables.  This lesson will work well for kinesthetic learners, visual learners and auditory learners.

Materials Needed

  • 4 foot deep column of water or swimming pool

  • 6 coins (penny, nickel, dime, quarter, half dollar, silver dollar) - Silver dollar optional

  • GoPro with waterproof housing

  • 2 to 3 students per group.

Time Needed

  • Prep Time: 10 minutes

  • Lesson: two class periods to discuss predictions and setup procedures for experiment

  • Activity: one class period

  • Assessment: Predictions, Data taking, Observations.

Project Instructional Plan

  1. Introduction: Hand out coins and ask students what order they think they will fall if dropped in a pool.

  2. Have student write down predictions and why

  3. Students will then discuss their predictions within their group of three.

  4. Have students create a material list & procedure for the experiment focusing on any variable that could affect their data.

  5. Have students create their own data table (if you are used to giving students pre-made data table, that is fine, but we have found that creating data charts is a useful skill for students)

  6. Take students to pool to do the trials. (If you do not have ready access to a pool, an aquarium can be used (just not as much fun).

  7. Students will then watch the videos using Quicktime to record their observations. (Note: when using quicktime, the arrow keys work great for slo-mo.)

Vocabulary

  • Friction

  • Resistance

  • Mass

  • Surface area

Assessment

Rubric for Science Process Skills

Student Work

https://www.youtube.com/watch?v=5mWuxAYH5zs&feature=youtu.be

Student Data

Students we already well versed in the scientific method and doing “canned” experiments. For this project we decided to pose the question “Which coins will fall the fastest in a pool?”.  We gave each group of 3 one bag of coins containing (1) penny, nickel, dime, quarter, half dollar & silver dollar.  Each student then predicted the order in which the coins would fall and why.   Each student then made his or her “pitch” to convince the other members of why they chose the order they did.  Students then created their own observation charts (this part took a lot of hand holding and revision).

Each group was required to come up with there own material list. One group decided to bring a smooth piece of wood to use to slide the coins off so they all hit the water at the same time and angle.  We thought this was a good idea and worked pretty well at the pool.  

Students then went down to the pool to film the 20 trials.  The footage was then imported to iMovie then slowed down so students could record their results.  Motivation was not a huge problem for this lesson, kids in a pool, what could be more motivating!  We have 60 minute classes so getting to the pool and doing the 20 trials was no problem, kids had extra time to film themselves jumping off the diving board.

Return to top