1. Conductor - is a material which contains movable electric charges. In metallic conductors such as copper or aluminum, the movable charged particles are electrons (see electrical conduction). Positive charges may also be mobile, such as the cationic electrolyte(s) of a battery, or the mobile protons of the proton conductor of a fuel cell. In general use, the term "conductor" is interchangeable with "wire. 2. Insulators – are non-conducting materials with few mobile charges and which support only insignificant electric currents. 3. Atom - is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons (except in the case of hydrogen-1, which is the only stable nuclide with no neutrons). 4. Electric charge - is a physical property of matter that causes it to experience a force when near other electrically charged matter. Electric charge comes in two types, called positive and negative. Two positively charged substances, or objects, experience a mutual repulsive force, as do two negatively charged objects. Positively charged objects and negatively charged objects experience an attractive force. 5. A simple circuit contains the minimum things needed to have a functioning electric circuit. A simple circuit requires three (3) things:

* A source of electrical potential difference or voltage. (typically a battery or electrical outlet) * A conductive path which would allow for the movement of charges. (typically made of wire) * An electrical resistance (resistor) which is loosely defined as any object that uses electricity to do work. (a light bulb, electric motor, heating element, speaker, etc.) 6. Electrical circuit - is a path which electrons from a voltage or current source follow. Electric current flows in a closed path called an electric circuit. The point where those electrons...

...Parallel Circuits
Name:_____________________________________________
Directions:
1. Go to the following website:
http://phet.colorado.edu/en/simulation/circuit-construction-kit-ac-virtual-lab
2. Click “Run now.”
You now have the raw material to create a circuit. Take a moment to look over the site and find all the different materials. To build a circuit you will need several wires, a light bulb, a voltage source, a voltmeter, and a non – contact ammeter. Play with it to see how to grab and manipulate these tools.
Click the reset all button.
A. Series Circuits
Build a simple series circuit that consists of 4-6 pieces of wire, 1 light bulb, and 1 battery (voltage source). In order to complete the circuit, the red circles at the end of each must overlap. Please note that the light bulb also has TWO circles. Your circuit is complete and working when the light comes on and the blue dots begin moving.
What do you think that the moving blue dots represent? (2 points)
Explain what a battery does in an electricalcircuit? Refer to page 606 in your textbook. (3 points)
Click in the Tools boxes to get a voltmeter and a Non-contact ammeter. Put the voltmeter near the battery and place the red tab at one end and the black at the other
What is the voltage (V)? (2 points)...

...ELECTRICAL CONDUCTORS
A conductor is an object or type of material which permits the flow of electric charges in one or more directions. For example, a wire is an electrical conductor that can carry electricity along its length.
Physics
All conductors contain electrical charges, which will move when an electric potential difference (measured in volts) is applied across separate points on the material. This flow of charge (measured in amperes) is what is meant by electric current. In most materials, the direct current is proportional to the voltage (as determined by Ohm's law), provided the temperature remains constant and the material remains in the same shape and state.
Copper is the most common material used for electrical.Silver is the best conductor, but it is expensive. It has a resistivity of 1.6×10−8 Ω⋅m. Because gold does not corrode, it is used for high-quality surface-to-surface contacts. However, there are also many non-metallic conductors, including graphite, solutions of salts, and all plasmas. There are even conductive polymers.
All non-superconducting materials offer some resistance and warm up during electric currents. Proper design of an electrical conductor takes into account the temperature of the conductor as well as the value of electric current. The motion of charges creates an electromagnetic field around the conductor that exerts a mechanical radial squeezing force on the...

...resist the flow of an electrical current. The quantity of resistance in an electric circuit determines the amount of current flowing in the circuit for any given voltage applied to the circuit. The resistance of an object is determined by the nature of the substance of which it is composed, its resistivity, accounting for its dimensions and its temperature. Resistivity is expressed in terms of Ohms / cm3 at 20ºC. Anelectrical conductor is any material that offers little resistance to the flow of an electric current. The difference between a conductor and an insulator, which is a poor conductor of electricity, is one of degree rather than kind, because all substances conduct electricity to some extent. A good conductor of electricity, such as silver or copper, may have a conductivity billions of times as great, or more, as the conductivity of a good insulator, such as glass or mica.
Method
We were set the task of investigating the factors that come into play when determining the resistance of a piece of wire. We would be provided with the necessary apparatus needed to carry out the investigations. The basic setup would involve a circuit with a set of cells connected in series with an ammeter and the piece of wire being investigated, and a voltmeter connected in parallel with the wire. The ammeter is placed in series with the wire. An ammeter has a low resistance, so that...

...How Does The Diameter Of Wire Affect The Resistance In A Circuit?
Introduction:
Some metals such as copper, silver and gold are very good conductors of electricity. This is because they all have only one electron on the outer shell. This means that they need only a tiny amount of energy in order to allow the electron to move. Non-metals, however, do not have free electrons, so even non-metals that only have one electron on their outer shell can still hold onto them tightly.
Aim Of The Investigation:
The aim of the investigation is to find out if there is a link between the thickness of a wire and resistance in a circuit.
Ohm’s Law:
Ohms law uses the formula of dividing the Voltage (V) by the current (I), then whatever the outcome of that is, is the resistance (R). For example Voltage = 4, Current = 2.65, 4÷2.65 = 1.509, therefore the resistance (R) = 1.509. We will use this formula in our experiment to find the resistance of the different wires and then once we have 3 different resistances from the given wire, we will work out the mean, in order to have a reliable answer with us, having removed any outliers the experiment may show.
Model Of Resistance:
Resistance measures a materials opposition to the flow of electric current. An example of a model of resistance is a motorway. For instance, if all the lanes are open on the road, there will be a steady flow and speed of the cars that are travelling on it. However, if there...

...Measurements of Capacitance and Inductance
Purpose: To use equipment and techniques to determine the structure of a hidden series RLC circuit and to measure the values of the various components in that circuit.
Theory:
To see how an RLC circuit works, consider the circuit in Figure 1 with the capacitor initially charged.
Fig. 1 RLC Circuit
Since there is a conducting wire connecting the negative side of the capacitor to the positive, a current will begin to flow in the counterclockwise direction. As it does, several things happen. The first is that the resistor will begin to strip energy from the current and convert it to thermal energy. The second is that the current through the inductor will result in a magnetic field. However, since the current is transient (not constant), the magnetic flux through the inductor is not constant, resulting in an emf across the inductor, pointing in the opposite direction of the voltage across the capacitor.
Once the capacitor is discharged, the emf in the inductor, in trying to prevent the change
in magnetic flux, will result in a current in the opposite direction. This causes an opposite charge to start building up on the capacitor. The negative charge will be on the upper plate. This transient current will continue to flow until the capacitor is charges and the magnetic flux through the inductor becomes zero. At this point, the capacitor current...

...
Experiment 5: RC Circuits
Abstract
The purpose of this lab is to learn and understand RC Circuits. An RC circuit is composed of at least one resistor and at least one capacitor. A capacitor is composed of two plates with either air or an insulator also known as a dielectric between the plates. We do not want the plates to be touching, because then we would only have a conductor. The insulator between the plates is also known as the dialectic, which affect how the capacitor will store charge. In an RC circuit, voltage will flow from the battery to the capacitor and through the resistor. When the capacitor is charging, the voltage across the battery is decreasing until the capacitor is fully charged. When the capacitor is fully charged, then the voltage through the battery is zero. That would also mean that the voltage of the circuit would drop until it is also zero. Now when the capacitor completely discharges, the voltage through the battery increases. We were able to measure the half-time of the charging and discharging of the capacitor by connecting the circuit to the oscilloscope with the signal generator providing the potential for the circuit. The time constant was calculated from the half-time of charging and discharging. The time constant is a measure of the length of time a capacitor took to charge and discharge. We used the average of...

...Parallel Circuits
Date Given: January 28, 2013
AIM: To investigate the circuits to tell whether the resistors are in parallel or in series also to determine the internal resistance of a 1.5V cell.
THEORY:
In this experiment it was expected of the experimenter to have a basic knowledge of circuits in both aspects theoretically and practically. A basic circuit comprises of a cell or power supply (some electric driving force) a load (some component that will use current) and connecting wires (these should be good conductors of electricity), as seen below.
Requirements of a circuit to function are it should be a closed circuit (a closed conducting path from negative to positive) also there has to be some potential difference as this causes the electrons to flow along the metal. This lab specifically investigates series circuits, parallel circuits and cells.
A series circuit has the same current flowing through all resistors adjacent to each other (in series), I=I1=I2…et cetera. The total potential difference (V) is equal to the sum of its individual potential differences, V=V1+V2. The individual potential differences are directly proportional to individual resistances, meaning each resistor in series has a corresponding voltage. The total resistance is equal to the sum of all resistances. A series circuit is shown...

...Electrical Engineering Fundamentals
Basic Concepts and Ohm’s Law
EEF 1
ECS1300L
Dr SMR Jones
Resistance
• In 1827 Georg Simon Ohm published the results of
experiments using the recently invented
electrochemical cell, invented by Italian Count
Alessandro Volta.
• Ohm found that the electrical current (I) flowing
through a sample of material was directly proportional
to the voltage (V) applied across the sample, i.e.
V
R
I
• This is known as “Ohm’s Law”.
• The constant of proportionality, R, is known as the
resistance of the sample
• Resistance is measured in Ohms, symbol [ V/A]
• We can write Ohm’s Law three ways:
• V/I = R,
V = IR,
I = V/R
Fundamentals of Electrical Engineering, SMRJ 2014
2
Resistivity
• Further experiment shows that the resistance increases in direct proportion to the
length of the sample and reduces in inverse proportion to the cross sectional area, i.e.
A
• The constant of proportionality, , is always the same for a given material.
is called the “resistivity” and has dimensions of m
R
• Resistivity is a measure of how hard it is for current to flow through a material under
the influence of an applied electric potential.
Fundamentals of Electrical Engineering, SMRJ 2014
3
Conductance and conductivity
• It is sometimes useful to use the reciprocal of resistance, i.e. the ratio of I/V
• We call this the conductance, G, i.e.
I
1
G
•
V
R
Conductance has units of...