Electrical Resistance Electrical resistance is a property of an electrical circuit that opposes the flow of current. Resistance involves collisions of the current-carrying charged particles with fixed particles that make up the structure of the conductor. Resistance is often considered as localized in such devices as lamps, heaters and resistors in which it predominates, although it is a characteristic of every part of a circuit, including connecting wires and electric transmission lines
Experiment on Electrical Resistance The electrical resistance of a material is its opposition to the flow of electric current (slowing the flow of electrons down). Resistance occurs when the electrons travelling along the wire collide with the atoms of the wire. These collisions slow down the flow of electrons causing resistance. Resistance is a measure of how hard it is to move the electrons through the wire. A current is the rate of the flow of charge (electrons) and the resistance controls
Science Coursework The Resistance of a Wire Aim: To find out how the length of a wire affects the resistance of it. Knowledge: Ohms Law is a mathematical equation that shows the relationship between Voltage, Current and Resistance in an electrical circuit. It is stated as: , V = I x R , R = V / I , I = V / R Where · V = Voltage · I = Current (I stands for INTENSITY) · R = Resistance In order to understand what Ohms Law is all about you need to understand electricity
Resistance of a Wire Introduction Resistance is the opposition a material offers to the flow of electricity. The electrical resistance of an object is not only by what material it's made of, but also by its shape. A very thin copper wire has more resistance than a thick copper wire of the same length. A very long copper wire has more resistance than a short one of the same thickness. Resistance is measured in Ohms. Variables There were three variables that our group was able to choose
material, however it does depend on the mass and density of the particular material. The resistivity of a particular material can be found by multiplying the resistance of the material by its cross sectional area, and then divided by it's length, this is shown in the equation below: ρ = (RA) ÷ l (where ρ= the resistivity of the material, R= the resistance of the material, A= the cross sectional area of the material and l= the length of the material) What is a resistivity survey and how does it work? A resistivity
The Resistance, of any conductor is given by the equation: R=V/I The electrons were gaining more and more energy from the rising voltage and atoms were beginning to collide faster and harder, with more power each time. The speed of collisions
The Galvanic Skin Response The simple psycho-galvanometer was one of the earliest tools of psychological research. A psycho-galvanometer measures the resistance of the skin to the passage of a very small electric current. It has been known for decades that the magnitude of this electrical resistance is affected, not only by the subject's general mood, but also by immediate emotional reactions. Although these facts have been known for over a hundred years and the first paper to be presented on the
old radio. He believes that he needs a resistance of 1.9 ohms which is not easily obtained. You are provided with some reels of resistance wire and are asked to plan and carry out an investigation to help the electrician solve this problem. When your investigation has been concluded you discover that a resistance of 28.5 ohms is also required to complete the repair. Show how you use the data from your investigation to also obtain this resistance. Introduction As mentioned in the
Investigating the Resistance of a Wire We have been given the task to investigate the resistance of different wires, I am firstly going to start by explaining what resistance is, why it occurs, what causes it, and how it can be used to our advantages. Resistance is a term used to describe the property that various materials possess to restrict or inhibit the flow of electricity. Whether or not a material obeys Ohm's law, its resistance can be described in terms of its resistivity.
is given by ΦB(PhiB). Now the value of the Schottky barrier height is dependent on the contact resistances of the metal and semiconductor under consideration. The idea of a schottky contact is that when metal and semiconductor are brought into contact with eac... ... middle of paper ... ...stead of one gap? Answer: The advantages of using several gap to measure the transfer or contact resistance using the TLM (transmission line method) are as follows: 1) A cylindrical TLM has been recently
job teaching mathematics at Erlangen University in 1805. He spent the next years looking for a better teaching position. He found what he was looking for in 1817 when a job was made available to him at Cologne Gymnasium. He now looked to research electrical current. In 1827 he published Die galvanishce Kette, mathematisch bearbeit (The Galvanic Circuit, Mathematically Treated). This was a mathematical description of conduction in circuits modeled after Fourier's study of heat conduction. This is also
diameter of approximately eight to twelve feet. The tubing is made from rolling strip metal, usually a carbon based steel, into cylindrical form and weld along its entire length. The longitudinal weld is made using a high-frequency induction electrical resistance method. The welding process produces a small amount of weld flash on both the inside and outside of the tube. This is removed from the outside diameter of the tube after welding by a carbide cutting tool contoured to the diameter of the tube
Resistance of a Wire Experiment Task To investigate how the resistance of a wire is affected by the length of the wire. Theory What is resistance? Electricity is conducted through a conductor, in this case wire, by means of free electrons. The number of free electrons depends on the material and more free electrons means a better conductor, i.e. it has less resistance. For example, gold has more free electrons than iron and, as a result, it is a better conductor. The free electrons
Factors Affecting the Resistance of a Wire The aim of this experiment is to investigate one factor that affect the resistance of a wire. I will do this by performing an experiment. First I will need to identify the factors that effect resistance. There are a few factors that affect the resistance, it is determined by the properties an object has. This is know as resistivity. The factors I can investigate are : Ÿ Temperature Ÿ Length Ÿ Cross-sectional area/width Ÿ Material
losses in the cable's metallic conductors. Temperature also has effects the resistivity of the conducting surface. Resistivity is a "bulk property of material describing how well that material inhibits current flow. This is slightly different from resistance, which is not a physical property. If one considers current flowing through a unit cube of material (say, a solid metal cube that measures 1 meter on each side), resistivity is defined as the voltage measured across the unit cube length (V/m) divided
How Thickness and Length Affect the Resistance of a Wire I plan to investigate how the length and thickness of a wire affects the resistance. I plan to do this by keeping the voltage the same by using a variable resistor and measure the current when varied lengths and thicknesses of wire is in a circuit ===================================================================== Variables ========= There are a few factors that can affect the resistance. These are; * Temperature *
Resistivity of a Wire Aim The aim of this experiment is to find out how the area of the cross section of the wire affects the resistance and also to find out the resistivity of the wire having found the resistance over a certain length and using a certain cross sectional area. I will also experiment to see how the length of the wire affects the resistance. Plan The first thing that I will do is to set up the apparatus as shown below. A,V Except for the experiment where I
observe things that will happen. I will look at a variety of possibilities, and hopefully I will find out what happens when the voltage is changed. Planning ======== Things the voltage may effect when varied are: Current Heat Resistance I have decided to change the voltage and measure the current. Prediction ========== I predict that if I double the voltage, then the current will also double. I predict that the voltage will be proportional to current. The current
R1 + R2 (in series): R1 + R2 (in parallel): Method: 1. Set up the apparatus 4 times as shown in the diagrams above 2. Set the power supply to 6v 3. Set the variable resistor to maximum resistance 4. Switch on the power and note the ammeter and voltmeter readings 5. Reduce the resistance of the variable resistor 6. Repeat steps 4, and 5 until at least five 8 sets of readings have been obtained 7. Change the setting of the apparatus as shown in the diagrams above, and perform
study is to understand and differentiate the resistance, voltage, and the current relations in circuits in series and in parallel II. THEORY Series circuits A series circuit is a circuit in which resistors are arranged in a chain, so the current has only one path to take. The current is the same through each resistor. The total resistance of the circuit is found by simply adding up the resistance values of the individual resistors: resistance of resistors in series : R = R1 + R2 + R3 + .