Sample-Formal-Lab Report

TENS 2146 electric automobile Devices and Measurements science lab 3 flowing and potential drop This report was prep atomic number 18d by L. beleaguer Fall 2009 Prof. R. Alba-Flores Team Members J. White, L. Wall Conducted on September 17, 2009 Submitted on September 24, 2009 abstraction In this science research lab disciples essayed with light emitting diodes. The scholar build a basic hitch with two conducts and immunitys in double. The endings showed that the potency is the akin in correspond. The items that were in series had the analogous incumbent.The results excessively showed that the underway from each tell apart could be summed up to equal the fall flow from the source. The experiment also helped the student to foregather the potential difference drop crosswise the diode was almost the same each time. This lab showed the effects of trustworthy and potency in a parallel tour. This experiment also showed how the ingeniousness was effected by changing the potential. Equipment and materials Multi thou berth Supply Connecting wires A bread board A 330 ohm immunity A l k ohm electric resistance 2 Red directs Theory A light-emitting diode ( guide), is an electronic light source.The set-back lead was built in the 1925 by Oleg Vladimirovich Losev, a radio technician who noniced that diodes utilise in radio receivers emitted light when certain was passed by means of them. The direct was introduced as a practical electronic component in 1962. All early devices emitted low-intensity red light, notwithstanding modern guides are avail fitting crossways the visible, ultraviolet and infra red wavelengths, with in truth high inventiveness. 1 prototype 1. Basics natural philosophy principle of an LED LEDs are semiconductors. They volition only work if placed in the correct direction.Placing the LED in the unlawful direction could potentially disablement it. The LED could also be damaged if it was not ins talled with the use of a electric resistance. They heap not be connected directly to a major power source. The anode is the positive end and the cathode is the electronegative end. LEDs are beneficial because they do not require much voltage to be illuminated. The LEDs are great for conservation of nil . When we subtract the LED voltage from the lend voltage it gives you the voltage that moldiness(prenominal) be dropped by the dropping resistor. A abate in voltage will result in a pass of the brightness of the bulb 1. lick 2 shows the electrical emblem and the positive shape of an LED. Figure 2. galvanizing symbol and the actual shape of an LED Ohms law is used to be able to calculate the authentic and the resistance crosswise each of the elements in the spell. To analyze the forget me drug It must be known that the voltage is the same in a parallel circuit. The true is the same in a series. The current by each class can be added up in order to determine the curren t from the source. From Kirchhoffs turn upd circuit law it can be situated that the sum of all of the voltage drops almost a closed loop must sum to equal zero.The objective of this lab was for the student to use their knowledge of items such(prenominal) as LEDs, series and parallel circuit configurations, Kirchhoffs laws, and Ohms law in order to the right way analyze and solve problems with granted circuit. 1 illume Emitting Diodes, http//en. wikipedia. org/wiki/Light-emitting_diode Procedure First thing we did in the lab was to create the circuit. We created the circuit by use resistors with determine of Rl = 330 ohms and R2 = l k ohms and also by placing the LEDs after the Resistors so there would be no damage done to the LEDs.This s shown in portend 3. The voltage show was set at 8 Volts and past we tested the ranges for voltage and current. To valuate voltage the meter has to be in Parallel with the circuit. Current is measurable by placing the Multimeter in ser ies with the circuit. In preparation for the experiment we built the circuit (shown below) use Multisim. We used shows to function all the required bars and used Ohms law of nature (E=I*R) to solve for the rest. In the lab we set up the same circuit by connecting the resistors and the LEDs in a parallel circuit to the power tote up.Most of the connections were done using the breadboard. We measured current by placing the Multimeter in series with the entire circuit. We set the Multimeter to measure amperes and turned the power on. We continued this using the 8, 6, 4, and 2 volts (adjusted on the power proviso) magical spell noting the brightness of the LEDs and writing down the value given by the Multimeter. We then connected the Multimeter in parallel with each resistor and LEDs to measure voltage. We set the multimeter to volts then cycled through 8, 6, 4, and 2 volts on the power planning and noted the reading for each connection.We then used Ohms Law to calculate the c urrent through as well as the resistance for each LED. We also cipher the entire current to watch out if it matched what we measured. Figure 3 Circuit built in the lab Sample Calculations To calculate the current through each resistor-LED branch, Ohms Law (V = IR) was used. In this Lab the equation used was I Rl = VRl / R 1 Example IRl = VRl / R1 = 5. 8 V / 3300 ? = 0. 0176 A To calculate the gibe resistance of each LED, Ohms Law was used. In this lab the equation RLED = V LED / ILED was used. ExampleRLED = V LED / ILED = 2. 18 v /0 . 0175 mA = 124. 57 ? To calculate the total current that the power submit was providing to the two branches, the equation IE = IRl + IR2 was used. In this lab the equation that was given to use was ILEDl = IRl . Example I LEDl + I LED2 = IE .0175 + . 0058 = . 0233 Simulation Results Multisim was used to set the simulations. Figures 4, 5, 6 and 7 shown the results obtained in the simulations. delay 1 summarizes these results. Figure 4. Power supply = 8 volts Voltages measured across R1 and R2 and currents through each LEDFigure 5 . Power supply= 6 volts Voltages measured across R1 and R2 and currents through each LED Figure 6. Power supply= 4 volts Voltages measured across R1 and R2 and currents through each LED Figure 7. Power supply= 2 volts Voltages measured across R1 and R2 and currents through each LED evade 1. Comparison of Pre-Lab simulations and actual Lab data Looking at the proportion chart above we can see that the voltage and the total current was close in value when flavor at the Pre-Lab and the Actual Lab.The actual Multisim simulation charts are printed and attached to this lab report. Looking at the comparison chart above we can see that the voltage and the total current was close in value when looking at the Pre-Lab and the Actual Lab. The actual Multisim simulation charts are printed and attached to this lab report. mop up In conclusion when simulating the circuit in actuality or in Multisim the LED volta ge, current, and brightness are affected by the fall of the voltage supply. By change magnitude the voltage supply the brightness of the LEDs also decrement in intensity.When determining the factors that are touch on in the brightness of the LED we must look at the circuit and see if the resistors and the LEDs are connected properly. We must also look at the value of the current passing through the current. To determine the current through the LEDs Ohms Law was applied. To find the current we must first measure the voltage and the resistance, and then after finding those two determine we divide the voltage by the resistance. Which Ohms Law is I (current) = V (voltage) / R (resistance).After finding the current in the LED it is seen that the current is almost equal to the resistor that is closes to that LED. I am in accordance with the measurement that was taken for the voltage supply of 8 volts, 6 volts, and 4 volts just now I disagree with the set for the voltage supply of 2 volts. The measurement peaceful in Multisim fo and the actual measurement value to a greater extent that the other voltage supply ranges. When the LEDs were reversed the resistor and the LED current and their voltages changed to O or r delinquent to there was zero or no flow of current and voltage.The voltage is what supply energy to the components in the circuit. So decreasing the amount of voltage will decrease the amount of energy current, and the amount of current is what determines the intensity of the LED. The pre-lab seemed to simulate more blameless values than the results of the values in Table 1. Due to the fact that there is more human value in the actual measurements than the reproduce ones plus the actual values have been round and round again. The simulated and actual values are truly close in value nevertheless do to human error the values are not and can not be exactly the same.