• Visit
    • Buy Tickets
    • Calendar
    • After Dark Thursdays
    • Exhibits
    • Artworks on View
    • Getting Here
    • Event Rentals
  • Education
    • Professional Development Programs
    • Tools for Teaching and Learning
    • Learning About Learning
    • Community Programs
    • Educator Newsletter
  • Explore
    • Browse by Subject
    • Activities
    • Video
    • Exhibits
    • Apps
    • Blogs
    • Websites
  • About Us
    • Our Story
    • Partnerships
    • Global Collaborations
    • Explore Our Reach
    • Arts at the Exploratorium
    • Contact Us
  • Join + Support
    • Donate today!
    • Membership
    • Join our donor community
    • Engage your business
    • Attend a fundraiser
    • Explore our reach
    • Thank you to our supporters
    • Host your event
    • Volunteer
  • Store
  • Visit
    • Buy Tickets
    • Frequently Asked Questions
    • Calendar
      • Today
      • This Week
      • After Dark Thursday Nights
      • Arts
      • Conferences
      • Cinema Arts
      • Free and Community Events
      • Fundraising Events
      • Kids + Families
      • Live Webcasts
      • Members
      • Ongoing + Series
      • Special Hours and Open Mondays
      • Private Event Closures
    • Hours
    • Getting Here
    • Museum Map
    • Reduced Rates & Community Day
    • Accessibility
    • Tips for Visiting with Kids
    • How to Exploratorium
    • Exhibits
    • Tactile Dome
    • Artworks on View
    • Cinema Arts
    • Kanbar Forum
    • Black Box
    • Museum Galleries
      • Bernard and Barbro Osher Gallery 1: Human Phenomena
        • Exhibition: Science of Sharing
          • Educator Activities
        • Tactile Dome
          • 1971 Press Release
        • Black Box
        • Curator Statement
      • Gallery 2: Tinkering
        • Curator Statement
      • Bechtel Gallery 3: Seeing and Listening
        • Curator Statement
      • Gallery 4: Living Systems
        • Curator Statement
      • Gallery 5: Outdoor Exhibits
        • Curator Statement
      • Fisher Bay Observatory Gallery 6: Observing Landscapes
        • Wired Pier Environmental Field Station
        • Curator Statement
      • PlayLists
        • All PlayLists
        • A Different Light
        • “We” or “Just Me”?
        • See Yourself in Cells
        • Greatest Hits: Gallery 2
        • Greatest Hits: Gallery 3
        • Greatest Hits: Gallery 4
        • Museum Map
    • Restaurant & Café
    • School Field Trips
      • Getting Here
        • Bus Routes for Field Trips and Other Groups
      • Prices and Discounts
      • Planning Guide
      • Reservations
        • Field Trip Request Form
      • Resources
    • Groups / Tour Operators
      • Group Visit Request Form
    • Event Rentals
      • COVID-Compliant Options
      • Full Facility & Gallery Bundles
      • Fisher Bay Observatory Gallery & Terrace
      • East Gallery
      • Bechtel Central Gallery
      • Osher West Gallery
      • Kanbar Forum
      • Weddings
      • Proms and School Events
      • Daytime Meeting & Event Options
      • Happy Hour on the Water
      • Rentals FAQ
      • Event Planning Resources
      • Rental Request Form
      • Download Brochure (pdf)
    • Exploratorium Store
    • Contact Us
    • Español
    • 繁體中文
    • 简体中文
    • 한국어
    • Français
    • Deutsch
    • Português
    • 日本語
  • Education
    • Professional Development Programs
      • Teacher Institute
        • About the Teacher Institute
        • Summer Institute for Teachers
        • Teacher Induction Program
        • Leadership Program
        • Teacher Institute Research
        • CA NGSS STEM Conferences
          • NGSS STEM Conference 2020
        • Science Snacks
          • Browse by Subject
          • Special Collections
          • Science Snacks A-Z
          • NGSS Planning Tools
          • Frequently Asked Questions
        • Digital Teaching Boxes
        • Meet the Teacher Institute Staff
        • Resources for Supporting Science Teachers
      • Institute for Inquiry
        • What Is Inquiry?
        • Inquiry-based Science and English Language Development
          • Educators Guide
            • Conceptual Overview
              • Science Talk
              • Science Writing
            • Classroom Video Gallery
              • Magnet Investigation
              • Snail Investigation
            • Teacher Professional Development
            • Project Studies
            • Acknowledgments
          • Conference: Exploring Science and English Language Development
            • Interviews with Participants
            • Plenary Sessions
            • Synthesis, Documentation, and Resources
        • Workshops
          • Participant Portal
          • Fundamentals of Inquiry
            • Summary Schedule
          • BaySci Science Champions Academy
          • Facilitators Guides
          • Commissioned Workshops
        • Resource Library
        • Meet the IFI Staff
      • Resources for California Educators
      • K-12 Science Leader Network
      • Resources for Supporting Science Teachers
      • Field Trip Explainer Program
    • Tools for Teaching and Learning
      • Learning Toolbox
      • Science Snacks
      • Digital Teaching Boxes
      • Science Activities
      • Tinkering Projects
      • Videos
      • Exhibits
      • Publications
      • Apps
      • Educator Newsletter
      • Exploratorium Websites
    • Educator Newsletter
    • Advancing Ideas about Learning
      • Visitor Research and Evaluation
        • What we do
        • Reports & Publications
        • Projects
        • Who we are
      • Center for Informal Learning in Schools
    • Community Programs
      • High School Explainer Program
      • Xtech
      • Community Educational Engagement
      • California Tinkering Afterschool Network
        • About
        • Partners
        • Resources
        • News & Updates
        • Further Reading
  • Explore
    • Browse by Subject
      • Arts
      • Astronomy & Space Sciences
        • Planetary Science
        • Space Exploration
      • Biology
        • Anatomy & Physiology
        • Ecology
        • Evolution
        • Genetics
        • Molecular & Cellular Biology
        • Neuroscience
      • Chemistry
        • Combining Matter
        • Food & Cooking
        • Materials & Matter
        • States of Matter
      • Data
        • Data Collection & Analysis
        • Modeling & Simulations
        • Visualization
      • Earth Science
        • Atmosphere
        • Geology
        • Oceans & Water
      • Engineering & Technology
        • Design & Tinkering
        • Real-World Problems & Solutions
      • Environmental Science
        • Global Systems & Cycles
        • Human Impacts
      • History
      • Mathematics
      • Nature of Science
        • Measurement
        • Science as a Process
        • Size & Scale
        • Time
      • Perception
        • Light, Color & Seeing
        • Listening & Hearing
        • Optical Illusions
        • Scent, Smell & Taste
        • Tactile & Touch
      • Physics
        • Electricity & Magnetism
        • Energy
        • Heat & Temperature
        • Light
        • Mechanics
        • Quantum
        • Sound
        • Waves
      • Social Science
        • Culture
        • Language
        • Psychology
        • Sociology
    • Browse by Content Type
      • Activities
      • Blogs
      • Exhibits
      • Video
      • Websites
      • Apps
        • Total Solar Eclipse
  • About Us
    • Contact Info
    • Our Story
    • Our History
      • 50 Years 1969–2019
    • Fact Sheet
    • Impact Report
    • Awards
    • Arts at the Exploratorium
      • Artworks on View
      • Artist-in-Residence Program
      • Cinema Arts
        • History and Collection
        • Cinema Artists-in-Residence
        • Resources and Collaborating Organizations
        • Kanbar Forum
      • Center for Art & Inquiry
        • Begin Here
          • Lessons
            • Bob Miller/Light Walk
            • Ruth Asawa/Milk Carton Sculpture
          • Workshops
      • Resonance
        • About the Series
        • See & Hear
        • Past Seasons
      • Over the Water
      • Black Box
      • Upcoming Events
      • Temporary Exhibitions
      • Arts Program Staff
      • Arts Committee and Advisers
    • Newsletter
    • Educator Newsletter
    • Press Office
    • Senior Leadership
    • Board of Trustees
    • Board of Trustees Alumni
    • Staff Scientists
    • Staff Artists
    • Partnerships
      • Building Global Connections
        • Global Collaborations
          • Projects
          • Approach
          • People
          • Impact
      • Partnering with Science Agencies
        • NASA
        • NOAA
      • Partnering with Educational Institutions
      • Osher Fellows
    • Exhibit Making
    • Institute for Inquiry
    • Teacher Institute
    • Online Engagement
    • Explainer Programs
    • Studio for Public Spaces
    • Job Opportunities
    • Become a Volunteer
    • Follow & Share
    • FY20 Audit Report
    • 990 FY19 Tax Return
    • Use Policy
      • Privacy Policy
      • Intellectual Property Policy
  • Join + Support
    • Donate today!
    • Membership
      • Membership FAQ
      • Member Benefits
      • After Dark Membership
      • Member Events
      • May Is for Members
    • Join our donor community
    • Engage your business
      • Corporate Membership
      • Luminary Partnerships
    • Attend a fundraiser
      • Wonder Funday
      • Science of Cocktails
      • Party at the Piers
        • Event Leadership and Host Committee
    • Explore our reach
    • Thank you to our supporters
    • Volunteer
      • Benefits
      • How to Apply
      • Application for Corporate Groups
      • Application for Internships
      • Application for Professional Societies
      • Application for School Groups & Clubs
      • Our Contract
      • Application for Individuals
      • Opportunities
  • Press Office
    • Press Releases
    • News Coverage
    • Events Calendar
    • Fact Sheet
    • Photographs
    • Press Video
    • Press Kits
    • Press Visits
    • Exploratorium Logos
    • Recent Awards
    • Praise for the Exploratorium
    • Join Our Press List
  • Store
 

Learn with us online while the Exploratorium is temporarily closed. You can help us reopen—donate today.

Exploratorium
Exploratorium
  • Visit
    • Buy Tickets
    • Calendar
    • After Dark Thursdays
    • Exhibits
    • Artworks on View
    • Getting Here
    • Event Rentals
  • Education
    • Professional Development Programs
    • Tools for Teaching and Learning
    • Learning About Learning
    • Community Programs
    • Educator Newsletter
  • Explore
    • Browse by Subject
    • Activities
    • Video
    • Exhibits
    • Apps
    • Blogs
    • Websites
  • About Us
    • Our Story
    • Partnerships
    • Global Collaborations
    • Explore Our Reach
    • Arts at the Exploratorium
    • Contact Us
  • Join + Support
    • Donate today!
    • Membership
    • Join our donor community
    • Engage your business
    • Attend a fundraiser
    • Explore our reach
    • Thank you to our supporters
    • Host your event
    • Volunteer
  • Store
Science Snacks
Science activity that demonstrates convection
Science activity that demonstrates convection
Science activity that demonstrates convection
  • Science activity that demonstrates convection
  • Science activity that demonstrates convection
  • Science activity that demonstrates convection

Convection Currents

Make your own heat waves in an aquarium.

Here's a simple and visually appealing way to show convection currents in water. Warmer water rising through cooler water bends light, allowing you to project its motion onto a screen.


Grade Bands: 
3-5
6-8
9-12
Subject: 
Chemistry
Materials & Matter
Earth Science
Oceans & Water
Physics
Heat & Temperature
Keywords: 
convection
density
exhibit-based
visualization
NGSS and EP&Cs: 
ESS
ESS2
CCCs
Patterns
Cause and Effect
Systems and System Models
Energy And Matter
Stability and Change

  • Facebook logo
  • Reddit logo
  • Twitter logo


Tools and Materials

  • Two alligator clip leads (wires with clips on the ends)
  • 3 or more C or D batteries
  • A pencil lead (.5 or .7 mm mechanical pencil refills work well)
  • Clear plastic or glass container with rectangular flat sides (such as a small aquarium)
  • Tap water
  • Tape
  • Light source, such as a flashlight (a Mini Maglite with the reflector removed will produce sharp images)
  • Projection screen or white poster board
  • Food coloring (in a small dropper bottle or an eyedropper)

Assembly

  1. Attach one end of each alligator clip lead to either end of a single pencil lead.
  2. Fill the container with water.
  3. Place the pencil lead and attached clips in the water. Position the pencil lead so it is suspended more or less horizontally underwater, and tape the wires to the top edges of the container to keep the lead in place.
  4. Shine the light source through the liquid, projecting the shadow of the pencil lead onto the screen or white poster board.
  5. Line the batteries up in a series, as pictured. Secure the batteries together with tape if you wish. Hold the ends of the alligator leads against the battery terminals to conduct electricity through the pencil lead. Connecting and disconnecting the clips from the batteries will turn your device on and off.

To Do and Notice

Connect your leads to the batteries to let the heat start! Observe the convection currents rising from the pencil lead. Try connecting and disconnecting the batteries to better see the convection currents.

You can also vary the orientation of the alligator clips and wires to see if this has any significant effect on the convection pattern.

Add a few drops of food coloring to the liquid and observe the effects.


What’s Going On?

Like air, water expands as it gets warmer, so it becomes less dense. Because the water warmed by the current flowing through the carbon rod is less dense than the surrounding colder water, the warm water is pushed upward to the surface by the colder water, which is more dense and descends due to gravity, causing the food coloring to move along with it.

Because the cold and warm water have different densities, they have different indices of refraction. Light bends (refracts) as it passes from warmer to colder water or colder to warmer water. When light is bent towards an area of the screen, that area becomes brighter. When light is bent away from an area of the screen, that area becomes darker. The positions of warm and cold water are constantly changing, so the images projected on the screen shimmer and flow like heat waves in air.


Going Further

A simple variation of this activity is to place a candle on a table and project its image onto a screen or wall with a flashlight. The point source of a Mini Maglite projects clear images of convection when used on a small-scale desktop experiment like this. Changing the distance from the point light source to the candle will change the magnification of the image of the convection currents projected.



Related Snacks

Science activity that visualizes convection cells
Pie-Pan Convection

Visualize the spectacular fluid motion of convection cells.


Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Attribution: Exploratorium Teacher Institute

  • Education
    • Teacher Institute
    • Tools for Teaching and Learning
      • Science Snacks
        • Browse by Subject
        • Special Collections
        • Science Snacks A-Z
        • NGSS Planning Tools
        • Frequently Asked Questions

Connect with us!

  •   Sign up for our educator newsletter
  •   Follow #ExploEDU
  •   Teacher Institute YouTube
  •   Teacher Institute Facebook
  •  teacherinstitute @exploratorium.edu
Exploratorium
Visit
Join
Give

Pier 15
(Embarcadero at Green Street)
San Francisco, CA 94111
(415) 528-4444

Contact Us

  • Plan Your Visit
  • Buy Tickets
  • Hours
  • Getting Here
  • Calendar
  • Tactile Dome
  • Store
  • About Us
  • Become a Member
  • Donate
  • Event Rentals
  • Jobs
  • Volunteer
  • Press Office

Get at-home activities and learning tools delivered straight to your inbox

© 2020 Exploratorium | Terms of Service | Privacy Policy | Your California Privacy Rights |