Currents From the Kitchen

Pre-lab

Purpose:

Which fruit will produce the most electric voltage?

Hypothesis:

The fruits with high acidity will produce the most electric voltage when they are connected with wires, copper and the nail.

Reasoning:

I think fruits with high acidity will produce the most electric voltage because citric acid is electrolytes that will help the production of electricity.

Materials:

• 1 voltmeter
• 2 wires
• 1 nail
• 1 copper strip
• at least 3 fruits/vegetables

Procedure:

1. Set up a voltmeter and use the 3-volt lead
2. Prepare your two or three different pieces of fruit
3. Select one fruit and insert the nail and the strip of copper on opposite sides of the fruit
4. Attach the wires to the voltmeter and connect each of the ends to the copper and the nail
5. Record the results
6. Repeat all the steps for each different piece of fruit

 

 

Results:

Fruit          Voltage

Apple               0.1 V

Nectarine         0.4 V

Plum                 0.3 V

 

Observations:

• the wire did not have to be fully secured onto the copper for the circuit to work (only had to be held against it)
• the electric voltage of the different fruits was not affected by placing the nail and copper in different places around the fruit
• the plum and nectarine were very juicy and slightly mushy which made the copper and nail wet
• the voltmeter moved very little when testing on various fruits
• the electric voltage of each fruit is in the same range

Conclusion:

After finishing testing various fruits, we found that the nectarine had the highest amount of electric voltage while the apple had the least amount of electric voltage. My hypothesis was more challenging to prove if my results reflected it since the fruits we used don’t have high acidity. Although,  from comparing and sharing with other classmates, it was mostly correct. They had experimented on a lemon, which had proven to have a higher electric voltage. Some things I wonder is if the juices from the previous fruits affect the result for other fruits and if the results would be altered if we put the copper or nail in the pit of the fruits (instead of the flesh).

 

Questions:

1. What is causing electrons to flow in this experiment?

The citric acid in the fruit act as electrolytes and with the copper and galvanized nail, it causes electrons to flow.

2. What are the independent, dependant and controlled variables in this experiment?

• Independent Variable- Type of fruit
• Dependent Variable- Electric voltage
• Controlled Variables- Nail, strip of copper and wires

3. How can we modify our experiment to improve our results?

We can use a larger variety of fruits and measure out the size of each piece (for consistency and accuracy).

4. What could be the sources of error or uncertainty in our experiment?

The sources of error or uncertainty in our experiment could be equipment that doesn’t work the way it is supposed to (ex. the wires and voltmeter).

5. How can I use this in my everyday life?

I can possibly use this in my everyday life for circumstances such as a power outage for a light source.