Science Fair Body:
Purpose
Electricity is one of the most important gifts that science has given to the mankind. It has become a part of everyday life and one cannot think of a world without it. Electricity has several uses in our day to day life. It is used for lighting rooms, working smartphones and domestic appliances such as washing machines, A/C units, dishwashers, and more. All these provide efficiency as well as comfort to people. Modern instrumentation like computers and robots have conjointly been developed due to electricity. Electricity provides means of amusement, radio, television and cinema, which are the most popular forms of entertainment are the result of electricity. Methods of modern communication and transportation have also been reformed and revolutionized by it. Electric trains and battery cars fast means that of travel. Large machines in factories are worked with the help of electricity. Essential things like food, cloth, paper and many other things are the products of electricity. Electricity plays a crucial role within the fields of medicines and surgery too — ex: X-ray, ECG. The use of electricity is increasing day by day. The purpose of this experiment is to analyse the different rates of resistance in different metals in order to
Hypothesis
Copper will have the best conductivity because of its low resistance properties while in a circuit. In the copper atom, the outermost energy zone, is only half filled, so many electrons are able to hold and carry electric currents throughout them. When an electric field is passed through a copper wire, the conduction of electrons accelerates towards the electropositive end, thereby creating a current. These electrons encounter resistance to their passage by colliding with other vacancies, lattice ions, and imperfections.
Literature review
It is important to fully understand the functionality of electricity in a circuit, along with some other complicated concepts regarding electricity as a whole. The electrical phenomenon is caused by a free flow of electrons in a current, traveling from one atom to another. Wires are made up of metal conductors which allow electricity to freely move.
Source: http://www.leonics.com/support/article2_2j/articles2_2j_en.php
A multimeter is used to measure many variables in a circuit, hence the name, multimeter. Multimeters can measure watts, volts, ohms, and amperes. Watts are the basic unit in electric, mechanical, and thermal power. Volts are used to measure electromotive force, or force of the through a conductor. An amp is the unit for measuring universal electricity. Ohms measure electrical resistance, which is how much electricity a wire holds back. Less of a resistance means higher electrical conductivity. For this project it is important to build a circuit with the various metals selected and measure ohms.
Source: http://www.newelectric.com/whats-the-difference-between-amps-volts-and-watts/
Evidently, there are also a lot of metal options to test the circuit. All metals conduct electricity. There are 118 elements on the periodic table of elements, and 91 of them are metals. For this experiment the metals will be metals that are easily accessible and used in everyday life. Such as but not limited to brass, steel, copper, silver and aluminum.
Source: https://www.metalsupermarkets.com/which-metals-conduct-electricity/
The common standard for the diameter or gauge of round wire is the American Wire Gauge. As strands of wire are made, they are braided through progressively smaller. In fact, the American Wire Gauge sizing system suggests that drawing procedure. For example, a size 22 AWG wire, smaller than 20 AWG, is drawn, theoretically, through 22 progressively smaller dies. Larger wire is drawn through fewer dies; hence, the lower-number gauge. Source: https://www.picwire.com/technical/tech-papers/wire-gauges
Material List:
1 meter 22 gauge wire
Zinc
Nichrome
Silver
Aluminum
Copper
Iron
Multi-meter
9V Battery
1 9V Volt Clip
2 Wires
One black for negative charge
One red for positive charge
Procedure:
Gather all of Materials listed above
Attach the volt clip to the 9V battery
Attach two wires, red for the positive charge and black for the negative charge
Attach alligator clamps to the ends of the red and black wires
Roll up the wire chosen to form a small coil
Clip the alligator clamps, which are connected to the wires connected to the volt clip on the battery, onto both ends of the coil, creating a circuit.
Pick up the multimeter.
Set multimeter setting on ohms.
Hold the multimeter on each of the the alligator clamps attached to the coil.
Take notes on the measurements on the reading of resistance on the multimeter.
Repeat with the rest of the wires and continue to take notes on data
Design Elements
Independent Variable: Type of metal and size of metal.
Dependant Variable: Level of electric conductivity in the metal.
Constants accounted for: Battery type, Battery voltage, temperature of room, temperature of wire, width of wire, length of wire, wire gauge, multimeter type, multimeter setting.
Results Section
Statistics:
Mean, Median, Mode, and Standard Deviation of Each Trial:
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Aluminum
0.000000024
0.000000021
0.000000022
0.00000002
0.000000022
Copper
0.000000012
0.000000013
0.000000014
0.000000013
0.000000015
Iron
0.000000026
0.000000023
0.000000023
0.000000023
0.000000023
Nichrome
0.00000011
0.00000013
0.00000012
0.00000015
0.00000012
Zinc
0.000000055
0.000000052
0.000000054
0.000000053
0.000000056
Silver
0.000000019
0.000000018
0.000000017
0.000000017
0.000000019
Standard Deviation
0.0000000368
0.0000000449
0.0000000409
0.0000000529
0.0000000407
Mean
0.000000041
0.0000000428
0.0000000416
0.000000046
0.0000000425
Median
0.000000025
0.000000022
0.0000000225
0.0000000215
0.0000000225
Mode
All values appear just once
All values appeared just once.
All values appeared just once.
All values appeared just once.
All values appeared just once.
Mean, median, and mode of each group:
Mean
Median
Mode
Aluminum
0.0000000218
0.000000022
0.000000022, appeared 2 times
Copper
0.0000000134
0.000000013
0.000000013, appeared 2 times
Iron
0.0000000236
0.000000023
0.000000023, appeared 4 times
Nichrome
0.000000126
0.00000012
0.00000012, appeared 2 times
Zinc
0.000000054
0.000000054
All values appeared just once.
Silver
0.000000018
0.000000018
0.000000019, 0.000000017, each appeared 2 times
Conclusion:
Electricity is key in modern day society. Humans all around the globe use electricity daily to make everyday activities easy and more efficient. The purpose of this experiment is to analyse which metals are the best for conductivity, and which ones make electricity itself more efficient.
It is hypothesized that copper is the best conductor. An electric current will flow through all metals, however they still have some resistance, meaning the current needs to be activated by a battery in order to keep flowing. The bigger the resistance, the harder electricity flows through a current, making it a bad conductor. Therefore a low resistance means an electric charge that flows easily, such as copper, thanks to its small electrical resistance, without much loss of energy.
The results support the hypothesis that copper is the best conductor out of other sampled tested for resistance. Based off of the means and medians of each metal (Figure 1), we can verify that copper indeed resulted in having the lowest resistance, which sheds light on the fact that copper is a better conductor than aluminum, iron, nichrome, zinc, and silver. Metals like Nichrome with high resistance are bad for electrical conducting, but have important thermal properties because of all the electricity absorbed from the current.
(Figure 1)
According to high ranking electrical experts, copper has the highest conductivity of any non-precious metal. This signifies that wires created out of copper provide a strong electric current without the major loss of electricity caused by some metals. This, combined with its low corrosion properties, makes copper the first choice as a conductor for electrical applications. Such as cables that provide electricity to houses, transformers and motor windings, and busbars.
Three sources that skewed results were: https://new.siemens.com/global/en/products/energy.html
https://www.electronics-tutorials.ws/blog/wheatstone-bridge.html
https://www.circuitspecialists.com/solderless-breadboards
These sources provided complicated information that needed conversion and analysis which resulted in some confusion around the topic of electrical conductivity, and whether or not resistance should be the variable to measure.
The standard deviation for trial 1 was 0.0000000368, for trial 2 was 0.0000000449, trial 3 was 0.0000000409, trial 4 was 0.0000000529, and trial 5 was 0.0000000407. While the means were for trial 1 0.000000041, trial 2 0.0000000428, trial 3 0.0000000416, trial 4 0.000000046, and trial 5 0.0000000425. The standard deviations for each trial were close to the means of each trial which proves that the data was expected and can be trusted.
Computers often use specific wire types to ensure functionality and efficiency. An interesting topic of research would be how computer wires use resistance in order to function, such as silicon, which is often used in computers and has a resistance in ohms of approximately 1.67.
The price of the metal also impacts whether or not it’s used in everyday electronics. Copper, for example, is very cheap, as well as effective. The price of metal by efficiency would be another important topic for investigation.
Finally, heat resistance. When a resistor absorbs electricity, it heats up, this can be manipulated into providing heat or making sure an electrical appliance doesn’t burn out, researching this to further boost one’s understanding of this topic would be interesting.
Bibliography
(2012, January/February). Retrieved December 17, 2018, from http://resources.schoolscience.co.uk/CDA/14-16/chemistry/copch0pg3.html
(2013, May 2). Retrieved December 17, 2018, from http://www.leonics.com/support/article2_2j/articles2_2j_en.php
Cable & Wire Gauges. (n.d.). Retrieved November 2, 2018, from https://www.picwire.com/technical/tech-papers/wire-gauges
Education.com. (2013, September 30). Resistivity: Is Copper the Best Metal Conductor? | Science project. Retrieved December 17, 2018, from https://www.education.com/science-fair/article/resistivity-iron-conduct-electricity-copper/
Information on copper | Copper Development Association. (2014, March 2). Retrieved December 17, 2018, from https://copperalliance.org.uk/
Makerspace & DIY. (n.d.). Retrieved December 17, 2018, from https://www.circuitspecialists.com/solderless-breadboards
Makerspace & DIY. (n.d.). Retrieved December 17, 2018, from https://www.circuitspecialists.com/solderless-breadboards
Reshift Media. (2018, October 30). Which Metals Conduct Electricity? (Video Update). Retrieved December 17, 2018, from https://www.metalsupermarkets.com/which-metals-conduct-electricity/
What's the Difference Between Amps, Volts and Watts? (2016, April 29). Retrieved December 17, 2018, from http://www.newelectric.com/whats-the-difference-between-amps-volts-and-watts/
Wheatstone Bridge Circuit and Theory of Operation. (2018, October 02). Retrieved December 17, 2018, from https://www.electronics-tutorials.ws/blog/wheatstone-bridge.html