Lab. Equipments Familiarization

Objective: To have a knowledge about the equipments of electrical circuit lab as Multimeter, Breadboard, Power supply, Resistors and their color and to learn the correct method to measure the circuit quantities with each instrument.

Equipments: a)  b) c) d) e)

The Digital Digital Multime Multimeter ter (DMM) (DMM) to measure measure electri electrical cal components components values. values. Breadboard Breadboard to make a connecti connection on between between electrical electrical circuit circuit part. The The DC Powe Powerr suppl supply y (PS) (PS).. Wires. Five Five resist resistors ors have have differ different ent value values. s.

Procedure: a. Measure Measure the values of given given five five resistor resistorss using using (DMM). (DMM).  b. Measure Measure the values values of given given five five resistor resistorss using using the color color code on each. c. Take the the actual values for for five five resistors resistors to compare compare them them with the the measuring measuring values. d. Setup DC DC PS on (3, (3, 6 & 8) volts (V) using using DMM DMM and compare compare the the values with Multimeter values.. e. Connect a resistor resistor has has value equal to to (1.8)KΩ (1.8)KΩ with with (PS) (PS) has value value equal equal to (5)V (5)V and place them on Breadboard. f. Measure Measure the values values of current current through through and and voltage voltage across across and dissipa dissipated ted power power of  resistor.

Data & Results: # 1 2

Resistor color   code -------------red , violet , red , Gold orange, orange, red, gold

Color code value (KΩ) 2.7±0.05 3.3±0.05

Experimental value (KΩ) 2.667 3.204

Theoretical value (KΩ) 2.6 7 3.2 5

Percentage error  (%) .119 .0142

3 Brown, gray, red, , gold 1.8±0.05 1.779 1.8 0.08 4 Brown own, black ,r ,red , gold old 1±0.05 0.988 1.0 0.0119 5 red, black , Brown , Brown 0.2±0.01 197.75Ω 4 .7 0 We can note from the last table that the actual values lie within tolerance color code values for all resistors. # ---------1 2 3

Value of DC PS using DMM (V) 3 6 8

Value of DC PS using Multimeter  (V) 2.99 5.99 8

Percentage error  (%) .33 .16 0

Sample of Calculations: For second resistor: Theoretical value = 3.25 KΩ. Experimental value = 3.204 KΩ. Percentage error = ({‫׀‬(theoretical value – experimental value)‫׀‬}/theoretical value)*100% = ({1.42% = 100%*(3.25/{‫׀‬(3.204 – 3.25) ‫׀‬ Color code value: orange orange Red Gold 3 3 *100 5% → value =3.3± 0.05 KΩ. *resistance between your hands 1- R anas =220 KΩ. 2- R hamza =290 KΩ. 3- R Mohammed =750 KΩ.

To calculate the value of current (I) through resistor we will use the Ohm’s low:

V = I*R where: I = current in Ampere (A). R = resistor in Ohm (Ω) V = voltage in Volt (V). →

I = V/R = 2.63mA.

To calculate the dissipated power (P) through the resistor we use the following low:

P = I*V → P = I*V = 4.99*2.63 = 13.1237mW.

Conclusion: In this experiment we learnt about the equipments of electrical circuit lab and use them to measure the components of the electrical circuit for example we connected the Ameter  in series with resistor to read the value of the current through it and connected the Voltmeter in parallel with resistor to read the value o f voltage across it. We faced many errors in this experiment as error in connect part of circuit and error in using the equipment and taking reading and using correct unit for our calculations ---etc.

Reference: Electrical circuit Lab. manual.