One of my favorite perks of homeschooling is being able to immerse our kids in hands-on STEM learning, whether we're on-site at an educational center or in our homeschool classroom. If you're short on ideas for a hands-on learning activity in your classroom, visiting an educational center like Discovery Cube LA may be what you need to jump-start your own creative thinking.
Today, we're taking a tips we learned during a recent visit to Discovery Cube LA's Science in Motion exhibit to study friction at home with this fun Rolling Resistance Experiment. What is friction? Friction is a force that resists motion between two objects when they come in contact with one another.
Exploring Science in Motion – Rolling Resistance Experiment
- Piece of sturdy cardboard or wood (size really isn’t all that important, but you want it to be at least 4” wide and 12” long)
- Stack of hard cover books that add up to about 4” high (again, total height isn’t all that important, but you don’t want it to be too much higher or shorter than 4”)
- Roll of wax paper
- Roll of foil
- Small ball or balls, such as tennis ball, baseball, bouncing ball, etc.
- Masking tape
- Stop watch
- Measuring tape or ruler
- Scrap paper
- Create your ground surface by placing the top of the wood or cardboard near the edge of the stack of books.
- Place a mark with a piece of tape on the ground at the bottom of your ramp. This will tell you where to position the ramp if it moves during your experiment, and will serve as the mark to stop the stopwatch at the end of the experiment. You may also want to mark a starting line to assure your ball releases at the same point each time.
- Next, place the ball in the same spot near the top of the ramp, holding it in place. Swiftly lift your hand (do not push the ball), allowing the ball to roll down on its own. Note: If the ball seems to roll down the ramp too quickly or slowly, adjust the height of the ramp by adding or removing a book or books.
- Create a chart to record your data. It might look something like this, but you can set it up however you would like this:
- While holding the stopwatch, time how long it takes for the ball to travel down the ramp and hit the lower mark. Record the time on your chart.
- Repeat the previous step twice, so you have a total of three trials using the cardboard surface for your ramp.
- Cover your ramp with foil, taping it into place. Put the ramp in the same position you had it before (just behind the masking tape on the floor) and test how long it takes for your ball to travel down the ramp to the mark three times. Record the data in your chart.
- Repeat this process a third time, but this time covering the ramp with wax or parchment paper.
- Average the amount of seconds required for the ball to roll down the ramp for each surface. Calculate the speed of the ball by dividing the distance traveled by the average number of seconds needed.
Examine your results. Which surface did you initially think would be the fastest surface? Which surface actually proved to be the fastest?
Have fun with your experiment by adding additional elements and chart the outcomes.
- If you have a long area to do the experiment, create a distance experiment to see how far the ball travels with each surface.
- Without changing the length or height of the ramp, how could you modify it further and continue your investigation?
- Can you find a way to put “pot holes” in your ramp? Speed bumps? Something that might represent gravel or sand?
What were our results? You can find them below. As you can see, our third trials were the fastest. Can you guess why by looking at our photos? Well, we did our experiment outside on a windy day. If you do your experiment outdoors as well, don't forget to factor in the weather.
About Discovery Cube LA
Discovery Cube LA is located at 11800 Foothill Blvd, Los Angeles, CA 91342. To learn more about Discovery Cube LA, their location and hours, and their current events, visit http://www.discoverycube.org/la/.
We were invited by Discovery Cube LA to be an official Discovery Cube Mom Ambassador. Portions of the material and expenses for this event have been provided courtesy of Discovery Cube LA. All opinions are our own.