This is a quick science experiment that only requires two items and a little practice. By the end of the experiment you’ll be able to pick up a ball using only a jar.
It doesn’t seem possible at first, but with the magic of centripetal force you’ll be able to make it happen.
Pick Up a Ball with a Jar Science Experiment Video
- Small Ball (we used a bouncy ball)
- Jar with a mouth that is larger than the ball (we used a pint canning jar)
Step 1 – Gather a small ball and a jar with a mouth that is bigger than the ball.
Helpful Tip: Bouncy balls are great for this experiment, as are pint sized canning jars.
Step 2 – First attempt the pick up the ball using the jar. You notice that it is difficult to do so, but you may be able to figure out the experiment with a little trial an error.
If you can’t pick up the ball, start again. This time place the jar over the ball on a hard surface.
Step 3 – Next, begin to move the jar in circular motions around the ball. The ball will eventually begin moving along the rim of the jar. As this happens, begin moving the jar faster and faster until the ball moves up into the jar.
Helpful Tip: This step will take practice and patience, but if you take your time you will eventually get the ball to move up into the glass.
Step 5 – Continue moving the jar in a circular motion and lift it off the table. You have just successfully picked up the bar, using just the jar.
Helpful Tip: While this experiment looks easy to perform, it does take practice to get it down. Don’t get discouraged if you can’t do it the first time. Instead keep practicing and you will eventually be able to pick up the ball.
How Does the Experiment Work?
When you spin the jar in a circle the ball will begin to move in circle along with the jar. When this happens, the jar pushes against the ball and the ball pushes against the jar. This creates a centripetal force which is greater than the force of gravity pulling down on the ball.
Therefore, it is centripetal force that allows you to pick up the ball with the jar.
If you stop (or slow down) the circular motion of the jar, the force of gravity will become greater than the centripetal force and the ball will fall out of the jar.
I hope you enjoyed the experiment. Here’s some printable instructions.