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Research Objective, Methodology And Data
Investigating the characteristics of a thermistor
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A level
Objective
The challenging task that I have finalised and undertaken for this
coursework is to build and test a sensor. I decided to build a sensor,
which would automatically change the speed of a fan by using a
thermistor. The main objective of the experiment was to monitor and
record the voltage change as the temperature changes. Specifically, as
predicting that when the temperature increases the voltage would
increase and thus the fan speed would increase too, thus causing a
cooling effect to the environment.
Data Information
Thermistors are thermally sensitive resistors and have, according to
type, a negative (NTC), or positive (PTC) resistance/temperature
coefficient. A thermistor is a type of resistor whose resistance
changes significantly when its temperature changes.
A negative temperature coefficient thermistor has a resistance that
decreases with increase of temperature. This is the most common type.
This is the type of resistor that I shall be evaluating and will be
using in my experiment.
A positive temperature coefficient thermistor has a resistance that
increases with increase of temperature. The resistance of a
semiconductor generally decreases with increase of temperature.
Semiconductors are therefore used to manufacture NTC thermistors.
When the temperature of a semiconductor is increased, the number of
charge carriers increases as more valence electrons gain sufficient
energy to break free from atoms to become conduction electrons. The
number of charge carriers increases as the temperature is increased so
the resistance of the semiconductor falls. Semiconductors are used to
make a wide range of electronic devices including electronic chips,
light emitting diodes and solid-state lasers. Communications, commerce
and entertainment have been revolutionised as a result of
semiconductor devices. In electrical terms, materials are classed as
either conductors or insulators or semiconductors.
Semiconductors are solid materials with conductivities in between the
very high conductivity of metals and the very low conductivities of
insulators. There are a variety of types of semiconductor, including
metal oxides as well as elements like silicon and germanium. In
insulators, essentially all the electrons are tightly bound to atoms
or ions, and none are free to move under an external electric field.
In effect, these materials do not conduct electricity at all. In
metallic conductors, essentially all the atoms are ionised, providing
free electrons, which move freely through the ions and can move under
an external electric field. These conduction electrons 'glue' the ions
together, and provide non-directional bonding which holds the material
together. They become shared amongst all the atoms in the material
instead of remaining attached to one atom.
Semiconductors differ from both insulators and metallic conductors.
Only a small proportion of atoms are ionised, so that although there
are conduction electrons they are relatively small in number and the
Most of the accusations were made against innocent people for reasons of economic conditions, teenage boredom, and personal jealousies. Of course there was also the fact that people weren’t aware of the certain mental illnesses caused by their environment. For example the one of the first people to be accused of witchcraft was a young girl named Betty Paris who one day became very ill with convulsive erogtism. Ergot is a fungus that invades growing kernels of rye, so it is very likely that she got sick from simply eating bread. Since people were scientifically unable to explain her sudden seizures and hallucinations she was accused of witchcraft.
Kent, Deborah. Witchcraft Trials: Fear, Betrayal, and Death in Salem. Library ed. Berkeley Heights, NJ: Enslow, 2009. Print.
The thermometer’s original temperature before coming in contact with an outside object is represented by T. ∆T/∆t is the average temperature of the digital thermometer. represents the temperature of the heat flowing object. In this lab, the temperature of the air is represented by Tair=T. To= Thand is the temperature of the hand.
Suzanna Berne’s article “Where Nothing Says Everything” discusses the sequence of events that Berne encounters as she attempts to pay her respects to the 9/11 tragedy. From the elements within her writing, Berne demonstrates the significant meaning of the World Trade Center’s absence. It is from her personal experience and play on words that she is able to accurately express her thesis. Within her piece, Suzanna Berne comes to the conclusion that the impact of 9/11 on the American people forces them to unite in order to overcome the loss of the World Trade Center along with the people who went down with it.
An electrode is a component of an electric circuit that connects the conventional wiring of the circuit to a conducting medium such as an electrolyte or a gas. The electrically positive electrode is called the anode and the negative electrode the cathode. If an anode and a cathode are placed in a solution of an electrolyte and a source of direct current is connected between them, the positive ions in the
The first term that I noted during the movie was Conductive Polymers. Conductive polymers are almost always organic meaning a large class of chemical compounds whose molecules contain carbon. These polymers have extended delocalized bonds which are bonds found in a molecule that do not belong to a single atom or covalent bond. They are conjugated systems of double bonds and in a aromatic systems. The conjugated systems are atoms covalently bonded with alternating single and double bonds. When the electrons are removed or added into the valence bands the electrical conductivity increases. The conductive polymer has a low conductivity until the electron is removed from the valence band called (p-doping) or (n-doping) until it becomes more conductive. The movement of the charges is what is responsible for electrical conductivity. These polymers are plastic which are organic polymers and with mechanical properties such as flexibility and elasticity.
Suddenly people seemed very paranoid and soon residents were placing blame on one another and accusing each other of witchcraft. In a fifteen month period between 1691 and 1692 nearly twelve dozen people were accused of witchcraft in or near Salem (Norton, p8).
Metals contain a sea of electrons (which are negatively charged) and which flow throughout the metal. This is what allows electric current to flow so well in all metals. An electrode is a component of an electric circuit that connects the wiring of the circuit to a gas or electrolyte. A compound that conducts in a solution is called an electrolyte. The electrically positive electrode is called the anode and the negative electrode the cathode.
The purpose of performing this lab was to find the specific heat capacity of an unknown metal.
The Salem Witchcraft Hysteria was a product of women’s search for power. This claim is supported by Lyle Koehler, from A Search for Power: The “weaker sex” in seventeenth-century New England (University of Illinois, 1980), explained and argues why this is true. Koehler mentions that the women were in search for more power and respect and power equality. She mentioned that the men were afraid of witches because they felt they were superior to them which brought in the question of who really was the superior gender. But really, the women accused others as being witches so as to gain more power from men. Basically, this showed that the women were not afraid of controlling or taking the power from men. In the seventeenth century, the men had power; so therefore, women did anything and would do anything to gain more power than the men. In puritan society, the only women with any significant power were mothers. They had powers not only in their homes but also in the public as long as they accused people of being witches. They also implicated others to achieve this power. An example that Koehler gave would be sociologist Dodd Bogart’s conclusion that “demon or witch charges are attempt to restore “self-worth, social recognition, social acceptance, social status and other related social rewards” is pertinent to the Salem village situation.
The objective of this experiment was to identify a metal based on its specific heat using calorimetry. The unknown metals specific heat was measured in two different settings, room temperature water and cold water. Using two different temperatures of water would prove that the specific heat remained constant. The heated metal was placed into the two different water temperatures during two separate trials, and then the measurements were recorded. Through the measurements taken and plugged into the equation, two specific heats were found. Taking the two specific heats and averaging them, it was then that
The aim of this essay is to analyse unitary urbanism and architecturally relevant ideas of the Situationist International movement through the critical reading of selected texts. To create context for the interpretation of the situationist techniques and experiments the “Situationist Manifesto” that was published in the year 1960 will be interrogated by using a broader range of their publications specifically concentrating on the critique of urbanism by the members of the movement.
Many US Women’s experiences have been shaped from the intersecting power inequalities that they have faced throughout their lives. These inequalities bring criticism, cruelty and sometimes death; however these women continue to fight for their rights through protests, activist organizations and by remaining composed when faced with adversities.
The photovoltaic effect, electricity can be created directly from sunlight. Some semi-conductor materials that are exposed to sunlight can create electron-hole pairs, which can be collected to produce electricity. This occurs when photons have energy above a certain threshold. These photons have shorter wavelengths. In silicon, the threshold for electron-hole production is in the infrared region of the electromagnetic spectrum.
For more than 60000 years, Aboriginal people have been lived with in the land called “Australia” with out invasion from outside world. However, from 1788 when European first came and settled on the land of Aboriginal as their new habitation which change the Aboriginal people life in many ways. The purpose of this report is to research and discuss about changing of Aboriginal people life after the arrival of the first fleet of European in 1788. This report will discuss the changing of the Aboriginal life from 1788 to 1901, which includes dispossession and protectionism. It will also highlight the struggle for right and freedom of Aboriginal people from 1901 to the present including Assimilation, Integration and Self-determination. In addition, it will identify role and achievement of Chatty Freeman and who influence Aboriginal’s culture to the forefront of society.