The opposition value for experiment 1.1, 1.2 and 1.3 calculated and was 93.23, 101.01 and 100.90 severally. The consequence of electromotive force addition on temperature was recoded and how power is lost as bosom was understood. How electrical current generate magnetic field was observed by utilizing compasses and explained. An experiment was besides carried out and explained in to how electromagnetic field is used to command electrical circuits affecting more than one circuit in a relay. The alteration of electrical energy to mechanical was besides investigated by utilizing an electric motor-fan.
Despite the celebrated experiment Benjamin Franklin, he did non invented electricity. Electricity exists of course. It has ever been about. A good illustration of electric flow that occurs of course is buoy uping. Lightening is a flow of negatrons between the land and clouds. When clouds hang-up against each other or other objects they become charged. When the possible difference between the clouds and land reaches a certain degree a flow of negatrons balances the charge, this exhibits a flash of visible radiation or lightening1.
Electrical systems and constituents can be classified into several capablenesss and used for many different applications. Electrical constituents and systems can be used to heat, power, sense, thrust, detect, indicate, to convey and have data2.
Electrical equipment such as visible radiation bulbs, batteries and electric generators are non needed for electric metropolis to be, although designed to utilize and tackle electric metropolis. If possible difference or electromotive force is maintained across a music director an electric flow occurs, Figure1. The currents magnitude depends on the electromotive force. The Ohm ‘s jurisprudence states that ”the current through a music director between the two points is straight relative to the possible difference across the two points ” . Therefore if the possible difference applied across a music director is changed the current will besides alter. If a device follows the Ohm ‘s jurisprudence the graph electromotive force vs current should hold a consecutive line3.
By rearranging the equation 1, electromotive force can be calculated ; in add-on the opposition of stuff can merely calculated by spliting the electromotive force to the current see equation 1.
Figure1. An electric potency across a conductor3
The two types of circuits are series and analogue. Entire opposition in series circuit can be determined by adding the single resistances opposition. To happen the opposition of two or more resistances connected in analogue, the amount of the reverse single opposition is used2, Equation2.
In electrical circuit some power is lost as heat. Resistance and heat loss is straight relative for a given Vs. Therefore if the V is increased the opposition will increase, this will so ensue in a great trade of heat being lost3.
When there is a demand to command more than one circuit, a relay is used. Relay is a switch operated by electric. The mechanical motion of a relay is frequently controlled by magnetic force. The flow of current through the relay spiral generates a magnetic field and changes the switch by pulling a lever. Relay aid one circuit to exchange to another circuit and run wholly separate from the initial circuit5.
Figure 2. Relay contact5
COM = Common, ever connect to this, it is the traveling portion of the switch.
NC = Normally Closed, COM is connected to this when the relay spiral is off
NO = Normally Open, COM is connected to this when the relay spiral is on
If an electrical current flows through a wire, a magnetic field is created due to the moving charges. Figure 3 demonstrates the magnetic Fieldss in a consecutive music director. The magnetic field for a consecutive music director circles around the music director. As illustrated from figure 4, a wire is coiled up to do a solenoid. The flow of the current determines the magnetic field way. Each cringle experiences its ain magnetic field and the entire magnetic field is the amount of single cringle. In add-on the magnitude of the entire magnetic field of a solenoid is straight relative to the figure of spirals a coiled wire has7.
Magnetic Field Around a Wire VRML Model
Figure 3. Magnetic Fieldss in Straight conductor7
Magnetic Field of a Solenoid VRML Model
Figure 4. Magnetic Fieldss in solenoid7
Electric motor is one of the really utile contraptions use electric power to turn in to mechanical energy. To understand how an electric motor work merely conceive of a nail wrapped with a wire and connected to a battery Figure 5. If the battery is connected to the wire, the nail would finally go a magnet and have a south and North Pole.
If the nail is suspended in the center of a horseshoe magnet as in figure 5, the north terminal of the nail would be repelled off from the horseshoe ‘s north terminal and attract to the south terminal of the horseshoe. By making this the nail would half bend and halt at the original topographic point. To keep a full bend the electromagnetic field of the nail should be flipped at a really precise minute. This is done merely by altering the way of the negatrons flow6.
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Figure 5. Electro magnet in a horseshoe magnet6
Experiment 1.1: Electrical circuit
As illustrated in figure 6, a series circuit was set up and one resistance was used across the circuit. Multi-meters were used to enter the electromotive force across the resistance and current. Five different electromotive forces in the scope of 2 to 12 Vs were applied and the current was recorded for each for each Vs.
Figure 6. Series one resistance circuit2
Similar process was used to enter the electromotive force and current for the 2nd experiment, this clip though two resistances were used.
Figure 7. Series two resistance circuit2
In the 3rd experiment two resistances was set up in a parallel circuit. Similar method to experiment one and two was used to enter the electromotive force and current.
Figure 8. Two resistances in parallel2
Experiment 2: Temperature vs. electromotive force
In the 4th experiment investigates the relationship between electromotive force and temperature across a resistance. Similar circuit to experiment was, but this clip one of the multi-meter was used set to enter temperature. A thermocouple as shown in figure 9 was used to observe the temperature alteration and this was fed to the multi-meter8.
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Figure 9. Thermocouple8
Experiment 3: Relay
Figure 10 shows the mechanism of the relay. A switch was used to command the relay by exchanging between the two circuits.
Figure 10. Diagram for connexion of experiment with relay and LEDs2
Experiment 4: Electric motor – Fan
An electric motor was used and given a power of 12 V. Electric current was controlled by a switch and the fan rotated as due to the magnetic field generated by the electric.
Experiment 5: Magnetism
In these experiment two methods was used to prove electro magnetic attraction of electric of the flow of current.
A wire used to flux electricity and magnetic compass was placed around the wire.
In the 2nd method a coiled wire was used and compasses was placed in the interior and outside of the coiled.
Table 1. Experiment one and two
Single resistance circuit
Two resistance in series
Two resistances in analogue
Note: The value of current highlighted for individual resistance at 6 Vs is an anomalousness.
Figure 11. Current V Voltage
Table 2. Resistance computation
Power in V
Parallel Circuit with 2 resistances
Below is resistance computation narrated ;
One obstructionist series circuit =
Two obstructionists Series circuit =
Two resistances Parallel Circuit
Using equation 2, R = ( Assuming R1 = R2 )
50.45 = R1 R1 +R2 = 100.90 ?
Experiment 2: Temperature vs. electromotive force
The graph shows a positive correlativity between electromotive force and temperature addition.
Figure 12. Voltage vs Temperature
Experiment 3: Relay
When the switch was turned on LED one turned on and when the switch turned of LED one visible radiation gone out and LED two turned on.
Experiment 4: Electric motor – Fan
The electric motor-fun started to whirl merely when the electric current started to flux. This was controlled by a switch for convenience.
Experiment 5: Magnetism
The consequences of electro magnetic attraction were observed in experiment 5. When a individual wire was used the compass acerate leafs aligned themselves towards the way of the current flow. In the coiled wire when the compass was placed inside the coiled wire the compass pointed towards the way of the electric flow. When the compasses was placed outside the solenoid the compasses experiences a great trade of warp in comparing with the individual wired overseas telegram.
Experiment 1.1 – 1.3 circuit
Figure 11 demonstrates an addition in electromotive force resulted on an addition in current. For the circuits with two resistances in analogue and series the graph was demoing a positive correlativity between the electromotive force addition and current addition. For the series circuit with one obstructionist there was an anomalousness when the electromotive force was set to 6 Vs. The addition in current at 6 Vs was excessively high, and this resulted on the graph being nonlinear. To do premises that the circuit obeys Ohmic jurisprudence the graph should be additive. Possible beginning of mistakes ;
Human mistake ( mistake when entering figures )
Faulty multi-meter being used
Faulty resistances or Faulty power supply reading
Experiment 2: Temperature V electromotive force
As illustrated in figure 12, as the electromotive force increase the temperature across the resistance besides increased. The temperature was straight relative to the electromotive force addition. Temperature addition was steady for every extra Vs applied for up to 6 Vs. Temperature addition was doubled so doubled when 8 Vs was applied. Some of the factors that can impact the sum of heat loss in a circuit are ;
Type of stuff used for wiring or resistance ( some stuff are good music directors and some are really good dielectric )
Wire diameter ( the smaller the diameter the harder for the negatrons to travel through )
Length of wiring
Temperature of the material/conductor ( lower temperature consequence in lower opposition and so lower heat loss ) 3
The crisp addition in temperature was due to possible mistakes ;
Leaving a peculiar electromotive force somewhat longer than the another
Breathing near the thermocouple ( addition in the overall temperature )
Experiment 3 Relay
Figure 10 demonstrates the relay experiment. Since the relay mechanism was really little to be observed by the bare eyes LED was used to bespeak if the electrical flow was exchanging in between the two circuits every clip the switch was hit. TQ team7 States that the entire magnetic field in a cringle is the amount of its single cringle. Since traveling charged atoms generate electromagnetic field many charged atoms bring forth a higher magnetic field. Therefore higher opposition in the wire coiling of a relay could do the relay non being able to pulling a lever. Higher opposition in relays could be caused by corroding or utilizing stuffs with low conduction.
Experiment 4 Electric motor-fan
The power used in the Electric motor-fan was DC current. The current in DC ever goes through one way. The electric-fan began revolving when the current starts to flux. The current flow was switched over, as the mutual opposition of the V switched over, it was expected the motor start running the opposite way alternatively the motor was stopped. The fan was perchance fitted with a device that merely allows a one way flow of current9. A rectifying tube was one of the possibilities that the electric motor-fan was fitted by. A rectifying tube is a two terminal device, with characteristics of some systematic transportation of electric metropolis character. A rectifying tube have a nothing opposition to electric flow in one way and high opposition ( 100 % ) opposition in the other way, hence electrical current flow merely in one way.
Experiment 5 Magnetism
As demonstrated from figure 3 and 4 electric current produces magnetic field. The compass used for the individual wire deflected and seen alining itself with the way of the electric current. By detecting the warp of the compass acerate leaf, the North and South Pole of the magnetic field was deducted10.
The end of the experiment was to understand the function of electricity in modern engineering. Resistance in series and parallel circuits were tried, electromagnetism and its applications explained. The experiments tax write-off narrated below ;
With the exclusion of one anomalousness result the circuits in experiment one obeys Ohmic jurisprudence, hence a additive graphs.
In series circuit the opposition value doubled when another resistance was added. As it can be observed from table 2 opposition values for the parallel with two resistances was about half the value for the series circuit with one resistance. Parallel circuit opposition was really little when compared with the opposition value in the series circuit with the same figure of resistances. The value for the resistances calculated as 93.23, 101.01 and 100.90 severally.
In experiment two, power dissipation promotes temperature addition.
Relay experiment demonstrates the control of more than one circuit by utilizing magnetic field of electric current.
Charged traveling atoms produce a magnetic field
Electric motor-fan converts electrical power in to mechanical by the aid on a magnet inside the motor.
Compasss used to detect the way of an electric current. The grater the cringle the grater the warp the compass experience. Figure 3 and 4 demonstrates the magnetic field in a individual wire and solenoid.