Active Amphibians!

Natural Electricity
Thousands of years ago the Greeks noticed that a type of stone called amber, attracted light objects, like feathers, after it was rubbed. The Greek word for amber is electron. Some materials, such as plastic, do not let electricity pass though, but if they rub against another material, a charge of static electricity can be produced. Static means staying in the same place. We experience static daily you may hear a crackling sound when you take off your jumper. Sometimes a spark is produced. Rubbing or friction cause static. You can generate your own static and watch the frogs jump.

Active Amphibians!
Step 1

Active Amphibians 01

 

Fold a piece tissue paper a number of times and cut out the shape of a frog. This way you can out several frogs at the same time.

 

Step  2

Active Amphibians 02

 

Cut out two lily pad shapes from green card. Cut out some flowers too. Put the lily pads on the card. Place the frogs on one lily pad.

 

Step 3

Active Amphibians 03

 

Cut a bird shape out of the yellow card. Attach it to the ping pong ball by threading string through both.

 

  

Step 4

 

Tie the other end of the string to the end of the stick. Make sure that the bird rests on top of the ball.

 

  

Step 5

 

A short distance away from the tissue paper shapes, rub the woolen cloth. Do this quite vigorously. This make the ball negatively charged.
 

Step 6

‘Fly’ the bird above the lily pond. Watch the uncharged frogs leap towards the bird. See if the frogs can leap to the other pad.

Why it works
All materials are made up of atoms that are electrically neutral. However, if atoms gain tiny particles called electrons, they become positively charged. Like charges will repel, unlike charges will attract. When the ping-pong ball is rubbed on the woolen cloth, it gains electrons and becomes negatively charged. The tissue paper frogs which are not charged, jump towards the ball when it is close by. Each time the frogs jump, they are charged in a process called induction.

Bright Ideas
Rub a balloon on woolen material, then hold it against a door. Now let go of the balloon. What happens?
How long does the effect of static electricity last?
Make a water bow. Rub a plastic spoon on wool. Hold the spoon near a stream of water from a tap. The water will bend towards the spoon. What happens if the water touches the spoon?