Investigate how the electrical resistance of a wire changes in relationship to it's length.
Physics Investigation Of Resistance Aim: to investigate how the electrical resistance of a wire changes in relationship to it's length. Prediction: I think that as the length of the wire increases so to will the resistance of it. I also believe that the rate at which the resistance of the wire increases will be directly proportional to the length. The graph to show this should therefore look something like this: Reason: with electricity, the property that transforms electrical energy into heat energy, in opposing electrical current, is resistance. A property of the atoms of all conductors is that they have free electrons in the outer shell of their structure. All metals are conductors and have an arrangement in similar form to this: As a result of the structure of all conductive atoms, the outer electrons are able to move about freely even in a solid. When there is a potential difference across a conductive material all of the free electrons arrange themselves in lines moving in the same direction. This forms an electrical current. Resistance is encountered when the charged particles that make up the current collide with other fixed particles in the material. As the resistance of a material increases so to must the force required to drive the same amount of current. In fact resistance, in ohms(R) is equal to the electromotive force or potential difference, in volts (V)
Resistance Coursework
Resistance Aim: In this investigation I want to find out how the length of and the width of the wire affects the resistance. Resistance: An explanation of what resistance would be that resistance is the opposition of a conductor to a flow of current. It is when traveling electrons in a wire collide with the atoms of a wire. The collisions between the electrons and the atoms cause the electrons to move slower, which causes resistance. So, resistance would be how hard it is to move electrons through a wire. Resistance is measured in Ohms ( ) Resistance = resistivity p (ohm metres) x length l Cross-sectional area A (square meters)* Current flows through a wire by a flow of electric charges. Wire is made up of a lattice of positive ions, surrounded by 'free' electrons. Ions can only vibrate about in their fixed positions but electrons are free to move randomly from one ion to another. When the battery is attached to the wire, the free electrons are repelled by the negative and attracted to the positive. They still have some random movement but they move slowly in the same direction through the wire with a steady drift. Ohm's Law: In 1827, a German physicist discovered relationship that the amount of steady current through a large number of materials is directly proportional to the potential difference, or voltage, across the
An investigation of the factors affecting the output of a transformer.
An investigation of the factors affecting the output of a transformer Planning Transformers are used in everyday life. They work on the principle of Electromagnetic field induction. Current (electrons) has an electromagnetic field. This field can manipulate the field of magnets. Also the field of magnets can manipulate the field of electrons in a similar way to how magnets interact. Transformers work by using the fields to transfer energy through the field lines: Wire induces a magnetic field in the iron core. Iron core. The field lines Are cut causing Wire an induced current. Causing a voltage in the first wire, causes a current. Around the current is a magnetic field, this induced a field in the iron core, the field lines of the core are then cut by a conductor (the second wire) and so a voltage is induced, in the reverse of how a voltage was induced in the transformer. In this way energy is transferred from electrical energy, to magnetic energy, back to electrical energy. The field lines must be continually moving in order to induce a current in the second coil (because a voltage is only induced when the field lines are being cut). The only way to do this is make the field lines change directions continually, in order to do that the electrons in the primary coil must be changing direction continually, and so we have to use alternating current. In order to make
Factors which affect the resistance of a wire
GCSE physics Coursework Factors which affect the resistance of a wire For my GCSE physics coursework I am going to investigate the factors that affect the resistance of a wire. What is electrical resistance? Electrical resistance is a measure of how a certain material opposes the flow of an electrical current flowing through it. Electricity is conducted through a conduct, in the case of my experiment the wire. The electricity is conducted across the material through free electrons; this is why metals are good conductors because they have free electrons. The more free electrons that a certain material has the better a conductor it is. When energy is passed through free electrons they start to vibrate and collide with other free electrons; this then happens across the whole of the wire and electricity is conducted across it, this is caused by a potential difference. Resistance is the result of energy loss as heat. It involves collisions between other free electrons, metal and impurities in the metal; these collisions convert some of the energy that the free electrons possess to heat. Resistance is a force that goes against the flow of a current in an electric circuit so that more energy is required to move the electrons around the circuit. When energy is passed to free electrons the free electrons pass the energy on to the atoms in a conductor causing them too
The aim of this experiment is to investigate how a change in the length of wire made from nichrome will affect the potential difference (voltage) and the current across that length, hence affecting the resistance.
PHYSICS INVESTIGATION INVESTIGATING THE RESISTANCE OF A WIRE AIM: The aim of this experiment is to investigate how a change in the length of wire made from nichrome will affect the potential difference (voltage) and the current across that length, hence affecting the resistance. Introduction: Resistance is the opposing force to the current in a circuit. The unit of resistance is the ohm (?). The electrical resistance of a conductor is defined by: R (Ohms) = Where I is the current flowing through the conductor when the Potential Difference across it is V. The ohm is defined as being: " The resitance of a conductor through which a current of one ampere is flowing when the PD across it is one volt, i.e. 1? = 1VA-1" Some conductors have resistances which depend on the current flowing through them, but the majority of conductors, notably metals, depends entirely on their physical condition. There are four factors which affect resistance in a metal wire: * Type of Material - The resistivity of various types of materials are different (see resistivity table further on). For instance, gold is a better conductor of electricity than copper, and therefore has less resistance. * Length - The longer a wire the more resitance it has as there is more matter for the electrons to collide with, so as to be able to pass. * Cross Sectional Area - The resistance of a material is
Investigate how mass affects the diameter of an impact crater.
PHYSICS COURSEWORK ASTEROIDS Asteroids, also known as small or minor planets are irregular bodies that vary in size and composition. They are usually found in the inner solar system among planets and primarily move in indirect orbits between the orbits of Jupiter and Mars, however some orbit relatively nearby to Earth. This is the prime concern with asteroids; where in the past collision with Earth has had tremendous affects and possibility of future collisions will always exist. This concern has been popularised in many forms and everyday the rate of technology intended to reduce the impact of any likely future asteroid collision is expanding. In order to recreate and demonstrate an increase or decrease in the impact of an asteroid, measurable by its crater size, my outcome variable is: How a chosen factor affects the diameter of an impact crater. There are many factors that have a form of influence: Mass - The gravitational potential energy stored by an object is significantly determined by the amount of matter it contains. As the mass increases, the potential increases, hence the kinetic energy increases causing an increase in the size of impact. Speed - The speed at which a falling object is travelling will have a major affect on the impact of crater. Hence crater size increases with increasing speed. Height - The speed of the object is dependant on the height at
What affects the resistance of a wire?
Planning Introduction Resistivity: It is a characteristic property of each material, and is useful in comparing various materials on the basis of their ability to conduct electric currents. High resistivity designates poor conductors. Resistivity () is proportional to the resistance (R) of a wire, multiplied by its cross-sectional area (A), and divided by its length (l). = RA / l. Since lengths are measured in centimetres in this experiment, resistivity would be expressed in units of ohm-centimetre. Conductivity is the reciprocal of resistivity, and it, too, characterizes materials on the basis of how well electric current flows in them. Good electrical conductors have high conductivities and low resistivities. Good insulators have high resistivities and low conductivities. (Britannica CD 2000 Deluxe Edition) Resistance: It is the property of an electric circuit that transforms electric energy into heat energy in opposing electric current. Resistance involves collisions of the current particles with the fixed particles that make up the structure of the conductor. The electromotive force or voltage (V) across a circuit, divided by the current (I) through that circuit, defines the amount of electrical resistance (R). R = V / I. Ohm is the common unit of electrical resistance, equivalent to one volt per ampere. The resistance of a wire is directly proportional to
Investigating The Heat Of Combustion Of Alcohols.
Investigating The Heat Of Combustion Of Alcohols Aim: To investigate the amount of heat given out by burning alcohols. I will do this by working out how much heat energy is produced per gram of alcohol. This will then be converted into heat energy per mole of alcohol. Introduction: Alcohols are part of a HOMOLOGOUS SERIES. The general formula for an alcohol is CnH2n+1OH. All alcohols have hydroxide ions, which acts as the functional group. The functional group is the group of atoms responsible for the characteristic reactions of a compound. Out of all the alcohols, ETHANOL is the most important. It is produced by fermentation or by the hydration of ethene. It will be interesting to see how ethanol burns with a flame. However I will also be testing to see how well methanol, propanol and pentanol burns with a flame. Hypothesis: I predict that all the reactions will be exothermic. This is from the knowledge I already have about the combustion of alcohols. I have worked out from using bond energies that in the combustion of alcohols, energy is released. With the alcohols a reaction can be written showing the combustion of the alcohol. I will go through each alcohol we used and make a prediction about the amount of energy it will give of using bond energies. For methanol the equation would be: Methanol + oxygen carbon dioxide + water + energy CH3OH + 3/2O2
An investigation into the factors affecting the resistance of a wire.
Richard Tandy September 2003 Year 11 Science Coursework An investigation into the factors affecting the resistance of a wire Introduction There are many factors that are known to affect the resistance of a wire. However, there are a few factors, which influence the resistance of a wire more than anything else. One factor, which determines the resistance of a wire, is the material in which the wire is made out of as the structure of metals influences resistance. The dimensions of the object and the temperature in particular also affect the materials resistance, as the temperature increases the molecules gain energy, which results in more collisions and therefore more resistance. Moreover, the length of the wire will also govern the amount of resistance created. Density too (how thick or thin the wire is), has a large affect on the amount of resistance. For example, a large surface area has less resistance because a small area has tightly packed atoms, which in turn rebound many of the electrons. The factors that can be investigated in Physics are those known as quantitative results - these are results that have continuous data (such as length). For this piece of coursework the factor that I will be investigating will be how the length of a wire will affect the resistance in which acts upon it. I
The aim of this investigation is to investigate the factors affecting the resistance of a wire.
Aim The aim of this investigation is to investigate the factors affecting the resistance of a wire. Background Information As the electrons in an electric current move around a circuit, they bump into the atoms in the wires through which they pass. Atoms of different elements slow down the electrons by different amounts. For example, electrons pass easily through copper wire but much difficultly through tungsten or nichrome wires. We say that copper has a lower resistance than nichrome or tungsten. This is why copper is used for the connecting wires and cables in electrical circuits. Electrons collide with atoms in the wire that vibrate more quickly. This causes the wire to warm up. If the resistance is high and the current is large, the wire may get red hot. Conductors like this, which provide a high resistance, are called resistors. Resistors vary the current in a circuit. The resistor that I will use in my investigation is called a rheostat. Some resistors obey the Ohm's law. A German scientist, Georg Ohm, investigated the resistance of various metal conductors. The unit that we use for resistance is called the Ohm in honour of Georg Ohm. The symbol for the ohm is ?, so five ohms is written as 5 ?. The equation to measure the resistance (Ohm's law) is: R = V Resistance = Voltage (Volts) I Current (Amps) The more resistance there is the
