Ken

The Effect of Electricity on Bacteria

Aim
To know what effect the electricity can have on Bacteria. (The relationship between voltage and the time takes to kill bacteria.)

As the voltage of electricity rises, the greater number of bacteria will die. (Therefore, the time takes to eliminate Bacteria will be reduced when I apply higher voltage.
 * Hypothesis**

Background
Few weeks ago, I knew how fast the bacteria grows from teacher and media (television). Even though you washed your hands

really clean, it may reduce the number of bacterias, but can't eliminate completely. In addition, when you do not use cup, but

directly use your mouth when you drink water, the bacteria may grows in the water. These facts made me surprised, so I wanted

to know what can eliminate the bacteria. Last week, I had a contact with electricity when I touched hair dryer with a little wet hand.

I am curious that whether the electricity can eliminate the bacteria or not, also how long it takes.

Materials
- cotton swab

- three petri dishes of bacteria

- the machine that can make electricity

- microscope

Procedure
1. Collect bacteria by swabbing on surfaces of lab tops, tables, and windows with cotton swab

2. Swab bacteria on petri dishes and store it in incubator for few days.

3. Put one piece of copper per each petri dish with bacteria.

4. Apply different electricity on each petri dish with bacteria by using the machine.

5. Use microscope to check whether the bacteria dies or not.

6. After bacteria dies, record the time taken on the graph.