Electrostatic Force: Making Salt and Pepper Dance

Grade Levels: 3 - 5

Objectives

  • Students will observe, infer, predict, experiment, formulate hypotheses, and identify and control variables.

Materials

  • Balloon
  • Wool cloth
  • Salt and pepper

Procedures

  1. Inflate the balloon and tie the end.
  2. Sprinkle a small amount of salt and pepper on a sheet of paper or on your desk top.
  3. Rub the balloon with the cloth.
  4. Bring the balloon within about an inch or two (2-5 cm) of the salt and pepper.
  5. Observe for a minute or two. You will need to caution your students to watch very carefully. Otherwise they will probably not notice that the same grains of salt and pepper are attracted to the balloon, repelled, then attracted again over and over.
  6. Explain what is happening and why:
    In this activity you will see the salt and pepper do a "dance" because of the following principles. The balloon, being rubbed with wool, takes on a negative charge. When it is held near the salt and pepper, the salt and pepper become charged positively by induction and will leap and cling to the balloon. As the salt and pepper remain in contact with the balloon, some of the negative charge (electrons) will drain off the balloon and onto the salt and pepper. The salt and pepper now have a negative charge – the same as the balloon – and will leap from the balloon. Notice that the salt and pepper do not simply fall, but rather they appear to be thrown from the balloon by some force. The force is the repelling action of the electrostatic charges for each other.

Excerpted from Hands-On Science Activities for Grades 3-4.

If you need to teach it, we have it covered.

Start your free trial to gain instant access to thousands of teacher-approved worksheets, activities, and over 22,000 resources created by educational publishers and teachers.

Start Your Free Trial

Follow us on:

Follow TeacherVision on Facebook
Follow TeacherVision on Google Plus

Highlights

Summer
Summer is almost over! Whether you still have several weeks until the first day of school, or just a couple, you can still focus on engaging students' minds while they're on vacation. Try our summer reading suggestions, math and science worksheets, and cross-curricular resource packets to prepare kids for what the next school year will bring!

August Calendar of Events
August is full of events that you can incorporate into your standard curriculum. Our Educators' Calendar outlines activities for each event, including: Ice Cream Sandwich Day (8/2), Pres. Obama's Birthday (8/4/1961), 2016 Summer Olympics (8/5-8/21), Friendship Day (8/7), International Art Appreciation Day (8/9), Activist Lucy Stone's Birthday (8/13/1818), Aviation Day (8/19), Tooth Fairy Day (8/22), Women's Equality Day (8/26). Plus, celebrate Back to School Month, Family Fun Month, Kids' Vision and Learning Month, Get Ready for Kindergarten Month all August long!

Videos
Interested in using different types of media in your classroom? We have a growing collection of videos, with related activities, for holidays and events, including: slavery & the Civil War, American History, U.S. Presidents, handwashing awareness, the Common Core, women's history, the American Revolution, and the environment. Enjoy!

Coding & Computer Science
Introduce your students to basic coding and computer science! Our Top 5 Free Coding Tools for Kids, Top 5 Free Coding Tools for Teens, and Hour of Code resources make a great introduction to the computer science skills all students will benefit from.