Analyzing Voltages Produced in Different Sizes of Fruits and Vegetables

© Aidan Singh, 2020

Abstract

This investigation is to determine whether fruits and vegetables that conduct electricity:

i. produce similar or different voltages, and

ii. have a relationship between its size and the amount of voltage it produces.

To conduct this investigation:

• I identified potatoes, apples and lemons, which are known to conduct electricity.

• I then created several completed circuits using the potato, apple and lemon as independent

conductors.

• In each circuit:

• I inserted a copper plated washer as a positive connector and a zinc plated screw as a

negative connector into each fruit and vegetable.

• I connected one test lead to the copper plated washer and connected the other end of

the test lead to the positive lead of a voltage meter.

• Using a second test lead, I connected one end to the zinc plated screw and the other

end to the negative lead of the voltage meter. The reading on the voltage meter was

recorded.

• This experiment was conducted multiple times, where I increased the number of whole or I

cut one whole into three slices. Each time I recorded the voltage.

• The results were then analyzed.

• At the conclusion of the investigation, I found that:

i. fruits and vegetables that conduct electricity produce different voltages, and

ii. the amount of voltage produced from a fruit or vegetable that conducts electricity is not

dependent on the size of the fruit or vegetable.

2

Research Purpose &

Impact

•To investigate whether there are alternative, cheaper and environmentally friendly sources to produce electricity to power small devices, and whether the size of these sources matters.

•In the past, people have analyzed voltages in fruits and vegetables but not many persons have discussed whether there is a relationship between the size of the fruits and vegetables and the amount of voltage produced.

Purpose

•Today, the number of battery-operated devices are at the highest. This number will continue to grow.

•Alternative sources of electricity that are cheaper, environmentally friendly and convenient can substitute the alkaline batteries, which are expensive, not environmentally friendly, and which can cause inconvenience.

Impact

3

Research Questions

•Are the voltages produced in fruits and vegetables similar or different?

Research Question #1

•Is there a relationship between the size of a fruit or vegetable and the amount of voltage the fruit or vegetable produces?

Research Question #2

4

Hypotheses

•If the water and acids in fruits and vegetables are different then the voltages will be different.

Hypothesis 1

•If the voltage in a fruit or a vegetable is the same, then the amount of voltage produced in the fruit or vegetable is not dependent on the size of the fruit or vegetable.

Hypothesis 2

5

Design & Methodology

(Materials)

• 1 whole potato

• 1 whole apple

• 1 whole lemon

• 1, 2, 3 potato slices

• 1, 2, 3 apple slices

• 1, 2, 3 lemon slices

• 6 copper washers

• 6 ¾ zinc-plated screws

• 6 low voltage test leads

• 1 small led bulb

• 1 digital multimeter

• 1 mini switch

Materials

6

Design & Methodology

(Variables)

• The different fruits and vegetables (apple, lemon, potato) and the different sizes.

Independent Variables

• Voltages produced by each fruit and vegetable.

Dependent Variable

• Copper washers and zinc plated screws in each fruit and vegetable.

Control Variable

7

Design & Methodology

(Procedure)

• Insert a zinc plated screw and a copper plated washer about 4/5th into a whole potato. The distance between the zinc plated screw and the copper plated washer is about 1 inch apart.

• Connect one end of a test lead with an alligator clip onto the zinc plated screw. Connect the other end of the test lead with an alligator clip to the negative lead of a digital voltage meter.

• Connect one end of a second test lead with an alligator clip onto the copper plated washer. Connect the other end of the test lead with an alligator clip to the positive lead of a digital voltage meter.

• Read and Record the voltage from the digital voltage meter.

• Repeat the steps [1 – 4] doing 3 trials. Replace the potato in [1] with:

• One slice of potato (a slice is about 1/3 of a whole)

• One whole lemon

• One slice of lemon

• One whole apple

• One slice of apple

Procedure

8

Design & Methodology

(Procedures 1 - 4)

9

Design & Methodology (Procedure 5

Improvement)

10

Data Collection

• I created a two-dimensional table.

• In the first column starting on the second row, I entered the names of the 3 fruits and vegetables (potato, lemon, apple).

• In the first row, starting on the second column I entered a label “voltage measurement for 1 whole”, “voltage measurement for 1 slice”.

• As I conducted each study, I recorded the voltage for the potato, lemon, apple.

Collecting Data Systematically

11

Data Collection

(Improvement)

• I found that that there were different voltage readings in different fruits and vegetables.

• I also found that the voltage measurements between one whole and one slice of the same fruit or vegetable did not vary much.

• To better understand this data, I repeated the experiment [1 – 4] by replacing the potato in with:

Study Improvement

Two whole potatoes Two whole lemons Two whole apples

Three whole potatoes Three whole lemons Three whole apples

Two slices of potatoes Two slices of lemons Two slices of apples

Three slices of potatoes Three slices of lemons Three slices of apples

The data I collected for each new experiment is entered into the correct corresponding cells.

12

Data Analysis and Results

from 1st

Study

• Following the data collection, I compared the data across the different cells to see if there are similarities or differences. I also plotted the data into graphs to visually compare and understand the data.

Data Analysis

Voltage measurements for

1 whole

Voltage measurements for 1

slice

Potato 0.92V 0.87V

Lemon 0.89V 0.83V

Apple 1.00V 0.93V

13

Data Analysis and Results

from Improved

Study

Voltage measurements for:

2 wholes 3 wholes 2 slices 3 slices

Potato 1.64V 2.25V 1.65V 2.29V

Lemon 1.74V 2.49V 1.50V 2.26V

Apple 1.97V 2.78V 1.79V 2.69V

14

Graphical Representation

from Study 1

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

0.90

1.00

Potato Lemon Apple

Vo

ltag

e M

easu

rem

ent

Vegetable and Fruits

Results of Study #1

1 whole 1 slice (about 1/3 of a whole)

15

Graphical Representation

from Combined

Studies1 whole 1 slice 2 wholes 2 slices 3 wholes 3 slices

Potato 0.92 0.87 1.64 1.65 2.25 2.29

Lemon 0.89 0.83 1.74 1.50 2.49 2.26

Apple 1.00 0.93 1.97 1.79 2.78 2.69

0.00

0.50

1.00

1.50

2.00

2.50

3.00

Vo

ltag

e M

easu

rem

ent

Results of Combined Studies

16

Findings

• Was able to support the existing studies on the value of fruits and vegetables acting as batteries in a number of applications.

• Showed that the amount of voltage produced from a fruit or vegetable that conducts electricity does not depend on the size of the fruit or vegetable.

• Found that when you add more fruits or vegetables in a series circuit, the voltage is not proportional to the added number (e.g., a potato with 0.92V when added to another potato with 0.84V produces a voltage of 1.64V rather than 1.76V).

In this investigation, I:

17

Real World Implications

• Fruit and vegetables could potentially power a clock or light a small bulb.

• In some instances, it can power a phone and provide persons in remote places where there is no rigid power connection such as a hiking trail with emergency access to other areas.

• Since size does not matter, a large number of simple circuits can be created from a small number of fruits and vegetables, for example, teachers in elementary and middle schools can use a few fruits and vegetables as the battery to teach students circuit diagrams in large classes.

• Fruits and vegetables are also cheaper and environmentally more friendly than a regular battery.

Implications

18

Safety Precautions

• I used a small kitchen knife to cut the potato, lemon and apple into onepiece to be used as part of the experiment. One of the risks of using theknife is the potential to cut and hurt myself.

• Another risk is the potential of the knife slipping and falling and injuring me.I hold the knife a certain way, so it didn’t cut me. To use the knife for theexperiment I carefully picked it up by the handle and held it firmly.

• After completely slicing the potatoes, lemons and apples, I carefully placedthe knife into a dishwasher to be cleaned.

• To minimize the risks of causing bodily injuries, I took extra care whenpicking up the kitchen knife, when using the kitchen knife and when puttingaway the kitchen knife. At all times, I had the blade pointing away from mybody and the tip pointing down. I used a damp towel under the cuttingboard when I was slicing the fruits and vegetables.

• I washed my hands frequently. Keeping workspace clean and disinfected. My parents were there to see if I was safe.

Safety Precautions

19