Measuring static electricity
The materials required for this science fair project:
- 1 balloon
- 1 copper plate 200mm x 300mm
- 1 ground connection
- 1 jumper wire with crocodile clips at both ends
- Human hair
- 1 small piece of polyester cloth
- 1 carpet
- 1 small piece of cotton cloth
- 1 small piece of nylon cloth
- 1 ceramic tile
- A flat tray
- 1 ruler
- 1 sheet of paper
- 1 paper knife
1. For this experiment, the independent variable is the type of material tested. The dependent variable is the number of pieces of paper picked up by the balloon. This is determined by simply counting the number of pieces. The constants (control variables) are the size of the balloon, the number of times the balloon is rubbed on the material tested and the weight of the paper bits.
2. The copper plate is connected to the ground connection using the jumper wire.
3. The sheet of paper is cut into 200 small pieces measuring 5mm x 5mm. The pieces are placed on the copper plate in order to ensure that all residual static electricity is discharged from paper. After that, the paper pieces are transferred to the flat tray.
4. The balloon is then inflated.The inflated balloon is also rolled across the copper plate to ensure that any residual static electricity is properly discharged before the experiment begins.
5. To begin the experiment, rub the balloon on the hair 5 times, in the same direction. Place the balloon on the cut pieces of paper. The paper pieces will be attracted to the balloon. Count the number of paper pieces sticking to the balloon and record the quantity in the table given below. Discharge the paper pieces on the copper plate and return them to the tray.
6. Discharge the balloon again by rolling it on the grounded copper plate.
7. Repeat procedures 5 and 6 by rubbing the balloon 5 times over the polyester cloth, carpet, cotton cloth, nylon cloth and ceramic tile in turn. Count the number of paper pieces picked up by the balloon and record the findings in the table below.