Do all materials conduct electricity? Let’s find out in this simple experiment
Things Required:
Spring-type clothespin
1 D-cell battery
Aluminium foil
Torch bulb
Masking tape
Scissors
Testing materials: rubber band, paper, coins ruler
Directions:
Cut a rectangle of aluminium foil, 24 inches × 12 inches (60 cm × 30 cm). Fold the aluminium piece in half lengthwise five times to form a thin strip 24 inches (60 cm) long. Cut the aluminium strip in half to form two 24 inches (30-cm) strips. Tape one end of each of the metal strips to the ends of the battery.
Wrap the free end of one of the metal strips around the base of the torch bulb. Hold the tape in place with the clothespin.
Test the electrical conductivity of the materials collected by touching the metal tip on the bottom of the torch bulb to one side of the material while touching the free end of the metal strip to the opposite side of the same material.
This Is What Happens:
The coins were the only materials that caused the bulb to glow.
Science Behind It:
An electric circuit is the path through which electrons move. A switch is a material that acts as a bridge or pathway for the electrons. When the switch is closed, the electrons move freely, but when it is open, the electrons stop. The only materials tested that allowed electrons to flow through them were those made of metal. Touching the paper clip to one side of a piece of metal and the tip of the bulb to the other side allowed the electrons to flow out of the negative part of the battery through the aluminium tape (conductor) into the bulb. The electrons continue their path from the bulb through the aluminium strip and back into the positive end of the battery. As long as there is no break in the system, the electrons continue to flow and the bulb will continue to glow.
